经济学原理曼昆第五版英文答案Chapter34

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经济学原理曼昆课后答案chapter4

经济学原理曼昆课后答案c h a p t e r4本页仅作为文档封面，使用时可以删除This document is for reference only-rar21year.MarchProblems and Applications1. a. Cold weather damages the orange crop, reducing the supply of oranges.This can be seen in Figure 4-6 as a shift to the left in the supply curve fororanges. The new equilibrium price is higher than the old equilibriumprice.Figure 4-6b. People often travel to the Caribbean from New England to escape coldweather, so demand for Caribbean hotel rooms is high in the winter. Inthe summer, fewer people travel to the Caribbean, since northern climesare more pleasant. The result, as shown in Figure 4-7, is a shift to the leftin the demand curve. The equilibrium price of Caribbean hotel rooms isthus lower in the summer than in the winter, as the figure shows.Figure 4-7c. When a war breaks out in the Middle East, many markets are affected.Since much oil production takes place there, the war disrupts oil supplies, shifting the supply curve for gasoline to the left, as shown in Figure 4-8.The result is a rise in the equilibrium price of gasoline. With a higherprice for gasoline, the cost of operating a gas-guzzling automobile, like aCadillac, will increase. As a result, the demand for used Cadillacs willdecline, as people in the market for cars won't find Cadillacs as attractive.In addition, some people who already own Cadillacs will try to sell them.The result is that the demand curve for used Cadillacs shifts to the left,while the supply curve shifts to the right, as shown in Figure 4-9. Theresult is a decline in the equilibrium price of used Cadillacs.Figure 4-8Figure 4-92. The statement that "an increase in the demand for notebooks raises the quantityof notebooks demanded, but not the quantity supplied" is false, in general. AsFigure 4-10 shows, the increase in demand for notebooks results in an increased quantity supplied. The only way the statement would be true is if the supplycurve were perfectly inelastic, as shown in Figure 4-11.Figure 4-10Figure 4-113. a. If people decide to have more children (a change in tastes), they'll wantlarger vehicles for hauling their kids around, so the demand for minivanswill increase. Supply won't be affected. The result is a rise in both priceand quantity, as Figure 4-12 shows.Figure 4-12Figure 4-13b. If a strike by steelworkers raises steel prices, the costs of producing aminivan rise (a rise in input prices), so the supply of minivans decreases.Demand won't be affected. The result is a rise in the price of minivansand a decline in the quantity, as Figure 4-13 shows.c. The development of new automated machinery for the production ofminivans is an improvement in technology. The reduction in firms' costsresults in an increase in supply. Demand isn't affected. The result is a decline in the price of minivans and an increase in the quantity, as Figure 4-14shows.Figure 4-14Figure 4-15d. The rise in the price of station wagons affects minivan demand becausestation wagons are substitutes for minivans (that is, there's a rise in theprice of a related good). The result is an increase in demand for minivans.Supply isn't affected. In equilibrium, the price and quantity of minivansboth rise, as Figure 4-12 shows.e. The reduction in peoples' wealth caused by a stock-market crash reducestheir income, leading to a reduction in the demand for minivans, sinceminivans are a normal good. Supply isn’t affected. As a result, both priceand quantity decline, as Figure 4-15 shows.4. Technological advances that reduce the cost of producing computer chipsrepresent a decline in an input price for producing a computer. The result is ashift to the right in the supply of computers, as shown in Figure 4-16. Theequilibrium price falls and the equilibrium quantity rises, as the figure shows.Figure 4-16Figure 4-17Since computer software is a complement to computers, the increasedequilibriumquantity of computers increases the demand for software. As Figure 4-17 shows, the result is a rise in both the equilibrium price and quantity of software.Since typewriters are substitutes for computers, the increased equilibriumquantity of computers reduces the demand for typewriters. As Figure 4-18shows, the result is a decline in both the equilibrium price and quantity oftypewriters.Figure 4-185. a. When a hurricane in South Carolina damages the cotton crop, it raisesinput prices for producing sweatshirts. As a result, the supply ofsweatshirts shifts to the left, as shown in Figure 4-19. The newequilibrium has a higher price and lower quantity of sweatshirts.b. A decline in the price of leather jackets leads more people to buy leatherjackets, reducing the demand for sweatshirts. The result, shown in Figure 4-20, is a decline in both the equilibrium price and quantity of sweatshirts.Figure 4-20c. The effects of colleges requiring students to engage in morningcalisthenics in appropriate attire raises the demand for sweatshirts, asshown in Figure 4-21. The result is an increase in both the equilibriumprice and quantity of sweatshirts.d. The invention of new knitting machines increases the supply ofsweatshirts. As Figure 4-22 shows, the result is a reduction in theequilibrium price and an increase in the equilibrium quantity ofsweatshirts.Figure 4-226. A temporarily high birth rate in the year 2005 leads to opposite effects on theprice of babysitting services in the years 2010 and 2020. In the year 2010, there are more 5-year olds who need sitters, so the demand for babysitting servicesrises, as shown in Figure 4-23. The result is a higher price for babysitting services in 2010. However, in the year 2020, the increased number of 15-year olds shifts the supply of babysitting services to the right, as shown in Figure 4-24. Theresult is a decline in the price of babysitting services.Figure 4-23Figure 4-247. Since ketchup is a complement for hot dogs, when the price of hot dogs rises,the quantity demanded of hot dogs falls, thus reducing the demand for ketchup, causing both price and quantity of ketchup to fall. Since the quantity of ketchup falls, the demand for tomatoes by ketchup producers falls, so both price andquantity of tomatoes fall. When the price of tomatoes falls, producers of tomato juice face lower input prices, so the supply curve for tomato juice shifts down,causing the price of tomato juice to fall and the quantity of tomato juice to rise.The fall in the price of tomato juice causes people to substitute tomato juice for orange juice, so the demand for orange juice declines, causing the price andquantity of orange juice to fall. Now you can see clearly why a rise in the price ofhot dogs leads to a fall in price of orange juice!Figure 4-258. a. Cigars and chewing tobacco are substitutes for cigarettes, since a higherprice for cigarettes would increase demand for cigars and chewingtobacco.b. An increase in the tax on cigarettes leads to increased demand for cigarsand chewing tobacco. The result, as shown in Figure 4-25 for cigars, is arise in both the equilibrium price and quantity of cigars and chewingtobacco.c. The results in part (b) showed that a tax on cigarettes leads people tosubstitute cigars and chewing tobacco for cigarettes when the tax oncigarettes rises. To reduce total tobacco usage, policymakers might alsowant to increase the tax on cigars and chewing tobacco, or pursue sometype of public education program.9. Quantity supplied equals quantity demanded at a price of $6 and quantity of 81pizzas (Figure 4-26). If price were greater than $6, quantity supplied wouldexceed quantity demanded, so suppliers would reduce their price to gain sales.If price were less than $6, quantity demanded would exceed quantity supplied, so suppliers could raise their price without losing sales. In both cases, the price would continue to adjust until it reached $6, the only price at which there'sneither surplus nor shortage.Figure 4-2610. a. If the price of flour falls, since flour is an ingredient in bagels, the supplycurve for bagels would shift to the right. The result, shown in Figure 4-27,would be a fall in the price of bagels and a rise in the equilibrium quantityof bagels.Since cream cheese is a complement to bagels, the rise in quantitydemanded of bagels increases the demand for cream cheese, as shown inFigure 4-28. The result is a rise in both the equilibrium price and quantityof cream cheese. So, a fall in the price of flour indeed raises both theequilibrium price of cream cheese and the equilibrium quantity of bagels.Figure 4-27Figure 4-28What happens if the price of milk falls Since milk is an ingredient in cream cheese, the fall in the price of milk leads to an increase in the supply of cream cheese. This leads to a decrease in the price of cream cheese (Figure 4-29), rather than a rise in the price of cream cheese. So a fall in the price of milk couldn't have been responsible for the pattern observed.Figure 4-29Figure 4-30b. In part (a), we found that a fall in the price of flour led to a rise in theprice of cream cheese and a rise in the equilibrium quantity of bagels. Ifthe price of flour rose, the opposite would be true; it would lead to a fallin the price of cream cheese and a fall in the equilibrium quantity ofbagels. Since the question says the equilibrium price of cream cheese has risen, it couldn't have been caused by a rise in the price of flour.What happens if the price of milk rises From part (a), we found that a fallin the price of milk caused a decline in the price of cream cheese, so arise in the price of milk would cause a rise in the price of cream cheese.Since bagels and cream cheese are complements, the rise in the price ofcream cheese would reduce the demand for bagels, as Figure 4-30 shows.The result is a decline in the equilibrium quantity of bagels. So a rise inthe price of milk does cause both a rise in the price of cream cheese anda decline in the equilibrium quantity of bagels.11. a. As Figure 4-31 shows, the supply curve is vertical. The constant supplymakes sense because the basketball arena has a fixed number of seats nomatter what the price.Figure 4-31b. Quantity supplied equals quantity demanded at a price of $8. Theequilibrium quantity is 8,000 tickets.c.Price Quantity Demanded Quantity Supplied$ 4 14,0008,0008 11,0008,000128,0008,000165,0008,000202,0008,000The new equilibrium price will be $12, which equates quantity demandedto quantity supplied. The equilibrium quantity is 8,000 tickets.12. The executives are confusing changes in demand with changes in quantitydemanded. Figure 4-32 shows the demand curve prior to the marketing campaign (D1), and after the campaign (D2). The marketing campaign increased the demand for champagne, as shown, leading to a higher equilibrium price and quantity. Theinfluence of the higher price on demand is already reflected in the outcome. It's impossible for the scenario outlined by the executives to occur.Figure 4-32。

曼昆_经济学原理答案_英文版chp4

Chapter 4The market forces of supply and demandSolutions to text problemsQZ What is a market? What does it mean for a market to be competitive? (page 60)A market is a group of buyers (who determine demand) and a group of sellers (who determine supply) of a particular good or service. A competitive market is one in which there are many buyers and many sellers so that each has a negligible impact on the market price.QZ List the determinants of the demand for pizza. Give an example of a demand schedule for pizza, and graph the implied demand curve. Give an example of something that would shift this demand curve. Would a change in the price of pizza shift this demand curve? (page 66)The determinants of the quantity of pizza demanded should include price, income, prices of related goods, tastes, expectations and the number of buyers.Here is an example of a demand schedule for pizza:Price of pizza slice Number of pizza slices demanded$0.00 100.25 90.50 80.75 71.00 61.25 51.50 41.75 32.00 22.25 12.50 0The demand curve is graphed in Figure 4.1.Figure 4.1Chapter 4: The market forces of supply and demand 31Examples of things that would shift the demand curve include changes in income, prices of related goods like soft drink or hot dogs, tastes, and expectations about future income or prices.A change in the price of pizza would not shift this demand curve; it would only move from one point to another along the curve.QZ List the determinants of the supply of pizza. Give an example of a supply schedule for pizza, and graph the implied supply curve. Give an example of something that would shift this supply curve. Would a change in the price of pizza shift this supply curve? (page 71)The determinants of the quantity of pizza supplied include the price of pizza, the prices of inputs into pizza production, the technology for producing pizza, expectations about things like the future price of pizza and the number of suppliers of pizza.Here is an example of a supply schedule for pizza:Price of pizza slice Number of pizza slices supplied$0.00 00.25 1000.50 2000.75 3001.00 4001.25 5001.50 6001.75 7002.00 8002.25 9002.50 1000The supply curve is graphed in Figure 4.2.Figure 4.232 Principles of Economics, Third edition, Instructor’s ManualExamples of things that would shift the supply curve include changes in prices of inputs like tomato sauce and cheese, changes in technology like more efficient pizza ovens or automatic dough makers, and changes in expectations about the future price of pizza.A change in the price of pizza would not shift this supply curve; it would only move from one point to another along the curve.QZ Analyse what happens to the market for pizza if the price of tomatoes rises. Analyse what happens to the market for pizza if the price of hamburgers falls. (page 75)If the price of tomatoes rises, the supply curve for pizza shifts to the left because of the increased price of an input into pizza production, however there is no effect on demand. The shift to the left of the supply curve causes the equilibrium price to rise and the equilibrium quantity to decline, as Figure 4.3 shows.Figure 4.3Chapter 4: The market forces of supply and demand 33 If the price of hamburgers falls, the demand curve for pizza shifts to the left because the lower price of hamburgers will lead consumers to buy more hamburgers and less pizza, but there is no effect on supply. The shift to the left of the demand curve causes the equilibrium price to fall and the equilibrium quantity to decline, as Figure 4.4 shows.Figure 4.434 Principles of Economics, Third edition, Instructor’s ManualQuestions for review (page 79)1 A competitive market is a market in which there are many buyers and many sellers so that each has anegligible impact on the market price.2The quantity of a good that buyers demand is determined by the price of the good, income, the prices of related goods, tastes, expectations and the number of buyers.3The demand schedule is a table that shows the relationship between the price of a good and the quantity demanded. The demand curve is the downward-sloping line relating price and quantity demanded. The demand schedule and demand curve are related because the demand curve is simplya graph showing the points in the demand schedule.4The demand curve slopes downward because of the law of demand—other things equal, when the price of a good rises, the quantity demanded of the good falls. People buy less of a good when its price rises, both because they can't afford to buy as much and because they switch to purchasing other goods.5 A change in consumers' tastes leads to a shift of the demand curve. A change in price leads to amovement along the demand curve.6The quantity of a good that sellers supply is determined by the price of the good, input prices, technology, expectations and the number of suppliers.7 A supply schedule is a table showing the relationship between the price of a good and the quantity aproducer is willing and able to supply. The supply curve is the upward-sloping line relating price and quantity supplied. The supply schedule and the supply curve are related because the supply curve is simply a graph showing the points in the supply schedule.8The supply curve slopes upward because when the price is high, suppliers' profits increase, so they supply more output to the market. The result is the law of supply—other things equal, when the price of a good rises, the quantity supplied of the good also rises.9 A change in producers' technology leads to a shift in the supply curve. A change in price leads to amovement along the supply curve.10The equilibrium of a market is the point at which the demand and supply curves intersect. At the equilibrium price, the quantity of the good that buyers are willing and able to buy exactly balances the quantity that sellers are willing and able to sell. If the price is above the equilibrium price, sellers want to sell more than buyers want to buy, so there is a surplus. Sellers try to increase their sales by cutting prices; that continues until they reach the equilibrium price. If the price is below theequilibrium price, buyers want to buy more than sellers want to sell, so there is a shortage. Sellers can raise their price without losing customers; that continues until they reach the equilibrium price. 11When the price of beer rises, the demand for pies declines, because beer and pies are complements and people want to buy less beer. When we say the demand for pies declines, we mean that the demand curve for pies shifts to the left as in Figure 4.5 below. The supply curve for pies isn'taffected. With a shift to the left in the demand curve, the equilibrium price and quantity both decline, as the figure shows. Thus the quantity of pies supplied and demanded both fall. In summary, supply is unchanged, demand is decreased, quantity supplied declines, quantity demanded declines, and the price falls.Chapter 4: The market forces of supply and demand 35Figure 4.512 Prices play a vital role in market economies because they bring markets into equilibrium. If the priceis different from its equilibrium level, quantity supplied and quantity demanded aren't equal. The resulting surplus or shortage leads suppliers to adjust the price until equilibrium is restored. Prices thus serve as signals that guide economic decisions and allocate scarce resources.Problems and applications (page 80)1 a The cyclone damages the banana harvest, reducing the supply of bananas. This can be seen inFigure 4.6 as a shift to the left in the supply curve for bananas. The new equilibrium price is higher than the old equilibrium price. Figure 4.6P r i c e o f p i e sQuantity of bananasP r i c e o f b a n a n a sQuantity of pies36 Principles of Economics, Third edition, Instructor’s Manualb People often go to the pictures during school holidays so demand for picture tickets is highduring school holidays. When school holidays end, fewer people go to the pictures. The result, as shown in Figure 4.7, is a shift to the left in the demand curve. The equilibrium price of picture tickets is thus lower when school holidays end, as the figure shows. Figure 4.7c When a war breaks out in the Middle East, many markets are affected. Since much oilproduction takes place there, the war disrupts oil supplies, shifting the supply curve for petrol tothe left, as shown in Figure 4.8. The result is a rise in the equilibrium price of petrol. With a higher price for petrol, the cost of operating a big car, like a Ford Falcon, will increase. As a result, the demand for used Ford Falcons will decline, as people in the market for cars won't find Falcons as attractive. In addition, some people who already own Falcons will try to sell them. The result is that the demand curve for used Falcons shifts to the left, while the supply curve shifts to the right, as shown in Figure 4.9. The result is a decline in the equilibrium price of used Falcons.Figure 4.8Quantity of theatre tickets P r i c e o f t h e a t r e t i c k e t sP r i c e o f p e t r o l Quantity of petrolChapter 4: The market forces of supply and demand 37Figure 4.92 The statement that ‘an increase in the demand for notebooks raises the quantity of notebooksdemanded, but not the quantity supplied’ is false, in general. As Figure 4.10 shows, the increase in demand for notebooks results in an increased quantity supplied. The only way the statement would be true is if the supply curve were perfectly inelastic, as shown in Figure 4.11. Figure 4.10P r i c e o f u s e d F o r d F a l c o n sQuantity of used Ford Falcons38 Principles of Economics, Third edition, Instructor’s ManualFigure 4.113 a If people decide to have more children (a change in tastes), they'll want larger vehicles forhauling their kids around, so the demand for station wagons will increase. Supply won't be affected. The result is a rise in both price and quantity, as Figure 4.12 shows. Figure 4.12Quantity of Station WagonsP r i c e o f S t a t i o n W a g o n sChapter 4: The market forces of supply and demand 39b If a strike by steelworkers raises steel prices, the costs of producing a station wagon rise (a risein input prices), so the supply of station wagons decreases. Demand won't be affected. The result is a rise in the price of station wagons and a decline in the quantity, as Figure 4.13 shows.Figure 4.13c The development of new automated machinery for the production of station wagons is animprovement in technology. The reduction in firms' costs results in an increase in supply. Demand isn't affected. The result is a decline in the price of station wagons and an increase in the quantity, as Figure 4.14 shows.Figure 4.14d The rise in the price of minivans affects station wagon demand because minivans are substitutesfor station wagons (that is, there's a rise in the price of a related good). The result is an increase in demand for station wagons. Supply isn't affected. In equilibrium, the price and quantity of station wagons both rise, as Figure 4.12 shows.P r i c e o f S t a t i o n W a g o n sQuantity of Station WagonsP r i c e o f S t a t i o n W a g o n sQuantity of Station Wagonse The reduction in peoples' wealth caused by a stock market crash reduces their income, leading toa reduction in the demand for station wagons, since station wagons are a normal good. Supply isn’t affected. As a result, both price and quantity decline, as Figure 4.15 shows. Figure 4.154 Technological advances that reduce the cost of producing computer chips represent a decline in aninput price for producing a computer. The result is a shift to the right in the supply of computers, as shown in Figure 4.16. The equilibrium price falls and the equilibrium quantity rises, as the figure shows. Figure 4.16Quantity of Station WagonsP r i c e o f S t a t i o n W a g o n sSince computer software is a complement to computers, the increased equilibrium quantity of computers increases the demand for software. As Figure 4.17 shows, the result is a rise in both the equilibrium price and quantity of software.Figure 4.17Since typewriters are substitutes for computers, the increased equilibrium quantity of computers reduces the demand for typewriters. As Figure 4.18 shows, the result is a decline in both theequilibrium price and quantity of typewriters.Figure 4.185 a When an outbreak of ‘foot and mouth’ disease hits sheep farms in New Zealand, it raises inputprices for producing woollen jumpers. As a result, the supply of woollen jumpers shifts to the left, as shown in Figure 4.19. The new equilibrium has a higher price and lower quantity of woollen jumpers. Figure 4.19b A decline in the price of leather jackets leads more people to buy leather jackets, reducing thedemand for woollen jumpers. The result, shown in Figure 4.20, is a decline in both theequilibrium price and quantity of woollen jumpers.Figure 4.20Quantity of woollen jumpers P r i c e o f w o o l l e n j u m p e r sQuantity of woollen jumpersP r i c e o f w o o l l e n j u m p e r sc Kylie wearing a woollen jumper raises the demand for woollen jumpers, as shown in Figure4.21. The result is an increase in both the equilibrium price and quantity of woollen jumpers. Figure 4.21d The invention of new knitting machines increases the supply of woollen jumpers. As Figure 4.22shows, the result is a reduction in the equilibrium price and an increase in the equilibriumquantity of woollen jumpers.Figure 4.22P r i c e o f W o o l l e n J u m p e r sQuantity of Woollen Jumpers Quantity of Woollen JumpersP r i c e o f W o o l l e n J u m p e r s6 A temporarily high birth rate in the year 2005 leads to opposite effects on the price of babysittingservices in the years 2010 and 2020. In the year 2010, there are more 5-year-olds who need sitters, so the demand for babysitting services rises, as shown in Figure 4.23. The result is a higher price for babysitting services in 2010. However, in the year 2020, the increased number of 15-year-olds shifts the supply of babysitting services to the right, as shown in Figure 4.24. The result is a decline in the price of babysitting services.Figure 4.23Figure 4.247Since tomato sauce is a complement for hot dogs, when the price of hot dogs rises, the quantity demanded of hot dogs falls, thus reducing the demand for tomato sauce, causing both price and quantity of tomato sauce to fall. Since the quantity of tomato sauce falls, the demand for tomatoes by tomato sauce producers falls, so both price and quantity of tomatoes fall. When the price of tomatoes falls, producers of tomato juice face lower input prices, so the supply curve for tomato juice shifts down, causing the price of tomato juice to fall and the quantity of tomato juice to rise. The fall in the price of tomato juice causes people to substitute tomato juice for orange juice, so the demand for orange juice declines, causing the price and quantity of orange juice to fall. Now you can see clearly why a rise in the price of hot dogs leads to a fall in price of orange juice!8 a Cigars and chewing tobacco are substitutes for cigarettes, since a higher price for cigaretteswould increase demand for cigars and pipe tobacco.b An increase in the tax on cigarettes leads to increased demand for cigars and pipe tobacco. Theresult, as shown in Figure 4.25 for cigars, is a rise in both the equilibrium price and quantity of cigars and pipe tobacco.Figure 4.25c The results in part (b) showed that a tax on cigarettes leads people to substitute cigars and pipetobacco for cigarettes when the tax on cigarettes rises. To reduce total tobacco usage,policymakers might also want to increase the tax on cigars and pipe tobacco, or pursue sometype of public education program.9Quantity supplied equals quantity demanded at a price of $6 and quantity of 81 pizzas (Figure 4.26).If price were greater than $6, quantity supplied would exceed quantity demanded, so suppliers would reduce their price to gain sales. If price were less than $6, quantity demanded would exceed quantity supplied, so suppliers could raise their price without losing sales. In both cases, the price would continue to adjust until it reached $6, the only price at which there is neither surplus nor shortage. Figure 4.2610 a If the price of flour falls, since flour is an ingredient in bagels, the supply curve for bagels wouldshift to the right. The result, shown in Figure 4.27, would be a fall in the price of bagels and arise in the equilibrium quantity of bagels. Since cream cheese is a complement to bagels, the rise in quantity demanded of bagels increases the demand for cream cheese, as shown in Figure 4.28.The result is a rise in both the equilibrium price and quantity of cream cheese. So, a fall in theprice of flour indeed raises both the equilibrium price of cream cheese and the equilibriumquantity of bagels.Figure 4.27Figure 4.28What happens if the price of milk falls? Since milk is an ingredient in cream cheese, the fall in the price of milk leads to an increase in the supply of cream cheese. This leads to a decrease in the price of cream cheese (Figure 4.29), rather than a rise in the price of cream cheese. So a fall in the price of milk couldn't have been responsible for the pattern observed.Figure 4.29b In part (a), we found that a fall in the price of flour led to a rise in the price of cream cheese anda rise in the equilibrium quantity of bagels. If the price of flour rose, the opposite would be true;it would lead to a fall in the price of cream cheese and a fall in the equilibrium quantity ofbagels. Since the question says the equilibrium price of cream cheese has risen, it couldn't have been caused by a rise in the price of flour.What happens if the price of milk rises? From part (a), we found that a fall in the price of milk caused a decline in the price of cream cheese, so a rise in the price of milk would cause a rise in the price of cream cheese. Since bagels and cream cheese are complements, the rise in the price of cream cheese would reduce the demand for bagels, as Figure 4.30 shows. The result is adecline in the equilibrium quantity of bagels. So a rise in the price of milk does cause both a rise in the price of cream cheese and a decline in the equilibrium quantity of bagels.Figure 4.3011 a As Figure 4.31 shows, the supply curve is vertical. The constant supply makes sense because thepicture theatre has a fixed number of seats no matter what the price.Figure 4.31b Quantity supplied equals quantity demanded at a price of $8. The equilibrium quantity is 800tickets. cPriceQuantity demandedQuantity supplied$4 1400 800 8 1100 800 12 800 800 16 500 800 20 200800The new equilibrium price will be $12, which equates quantity demanded to quantity supplied. The equilibrium quantity is 800 tickets.P r i c e o f p i c t u r e t h e a t r e t i c k e t sQuantity of picture theatre tickets 80012The executives are confusing changes in demand with changes in quantity demanded. Figure 4.32 shows the demand curve prior to the marketing campaign (D1), and after the campaign (D2). The marketing campaign increased the demand for champagne, as shown, leading to a higher equilibrium price and quantity. The influence of the higher price on demand is already reflected in the outcome.It's impossible for the scenario outlined by the executives to occur.Figure 4.3213 At equilibrium Q S=Q D. Therefore here:1400 + 700P = 1600 – 300P1000P = 200P = $0.20The equilibrium price is $0.20 per bar of chocolate. Substitute this into either Q S or Q D to get the equilibrium quantity of 1540 bars of chocolate.。

曼昆经济学原理英文版答案

曼昆经济学原理英文版答案As the creator of the Baidu Wenku document "Principles of Economics by Mankiw (English Version) Answers", I would like to provide a comprehensive guide to the solutions of the questions in the book. This document aims to help students better understand the principles of economics and improve their problem-solving abilities.Chapter 1: Ten Principles of Economics。

1. People face trade-offs.2. The cost of something is what you give up to get it.3. Rational people think at the margin.4. People respond to incentives.5. Trade can make everyone better off.6. Markets are usually a good way to organize economic activity.7. Governments can sometimes improve economic outcomes.8. The standard of living depends on a country's production.9. Prices rise when the government prints too much money.10. Society faces a short-run trade-off between inflation and unemployment.Chapter 2: Thinking Like an Economist。

曼昆经济学原理英文版教案加习题答案第4章THE MARKET FORCES OF SUPPLY AND DEMAND

51WHAT’S NEW IN THE S EVENTH EDITION:The In the News feature “Price Increases after Disasters” has been updated with a new article.LEARNING OBJECTIVES:By the end of this chapter, students should understand:➢ what a competitive market is.➢ what determines the demand for a good in a competitive market.➢ what determines the supply of a good in a competitive market.➢ how supply and demand together set the price of a good and the quantity sold.➢ the key role of prices in allocating scarce resources in market economies.CONTEXT AND PURPOSE:Chapter 4 is the first chapter in a three-chapter sequence that deals with supply and demand and how markets work. Chapter 4 shows how supply and demand for a good determines both the quantity produced and the price at which the good sells. Chapter 5 will add precision to the discussion of supply and demand by addressing the concept of elasticity —the sensitivity of the quantity supplied and quantity demanded to changes in economic variables. Chapter 6 will address the impact of government policies on prices and quantities in markets.The purpose of Chapter 4 is to establish the model of supply and demand. The model of supply and demand is the foundation for the discussion for the remainder of this text. For this reason, time spent studying the concepts in this chapter will return benefits to your students throughout their study of economics. Many instructors would argue that this chapter is the most important chapter in the text.THE MARKET FORCES OF SUPPLY AND DEMAND52 ❖Chapter 4/The Market Forces of Supply and DemandKEY POINTS:• Economists use the model of supply and demand to analyze competitive markets. In a competitive market, there are many buyers and sellers, each of whom has little or no influence on the market price.• The demand curve shows how the quantity of a good demanded depends on the price. According to the law of demand, as the price of a good falls, the quantity demanded rises. Therefore, the demand curve slopes downward.• In addition to price, other determinants of how much consumers want to buy include income, the prices of substitutes and complements, tastes, expectations, and the number of buyers. If one of these factors changes, the demand curve shifts.• The supply curve shows how the quantity of a good supplied depends on the price. According to the law of supply, as the price of a good rises, the quantity supplied rises. Therefore, the supply curve slopes upward.• In addition to price, other determinants of how much producers want to sell include input prices, technology, expectations, and the number of sellers. If one of these factors changes, the supply curve shifts.• The intersection of the supply and demand curves determines the market equilibrium. At the equilibrium price, the quantity demanded equals the quantity supplied.• The behavior of buyers and sellers naturally drives markets toward their equilibrium. When the market price is above the equilibrium price, there is a surplus of the good, which causes the market price to fall. When the market price is below the equilibrium price, there is a shortage, which causes the market price to rise.• To analyze how any event influences a market, we use the supply-and-demand diagram to examine how the event affects equilibrium price and quantity. To do this we follow three steps. First, we decide whether the event shifts the supply curve or the demand curve (or both). Second, we decide which direction the curve shifts. Third, we compare the new equilibrium with the initial equilibrium.• In market economies, prices are the signals that guide economic decisions and thereby allocate scarce resources. For every good in the economy, the price ensures that supply and demand are in balance. The equilibrium price then determines how much of the good buyers choose to consume and how much sellers choose to produce.Chapter 4/The Market Forces of Supply and Demand ❖ 53CHAPTER OUTLINE: I. Markets and CompetitionA. What Is a Market?1. Definition of market: a group of buyers and sellers of a particular good or service.2. Markets can take many forms and may be organized (agricultural commodities) or lessorganized (ice creamB. What Is Competition?1. Definition of competitive market: a market in which there are so many buyers andso many sellers that each has a negligible impact on the market price.2. Each buyer knows that there are several sellers from which to choose. Sellers know that each buyer purchases only a small amount of the total amount sold.C. In this chapter, we will assume that markets are perfectly competitive.1. Characteristics of a perfectly competitive market:a. The goods being offered for sale are exactly the same.b. The buyers and sellers are so numerous that no single buyer or seller has any influence over the market price.2. Because buyers and sellers must accept the market price as given, they are often called "price takers."3. Not all goods are sold in a perfectly competitive market.a. A market with only one seller is called a monopoly market.b. Other markets fall between perfect competition and monopoly.54 ❖ Chapter 4/The Market Forces of Supply and DemandD. We will start by studying perfect competition.1. Perfectly competitive markets are the easiest to analyze because buyers and sellers take the price as a given.2. Because some degree of competition is present in most markets, many of the lessons that we learn by studying supply and demand under perfect competition apply in morecomplicated markets.II. DemandA. The Demand Curve: The Relationship between Price and Quantity Demanded1. Definition of quantity demanded: the amount of a good that buyers are willing andable to purchase.2. One important determinant of quantity demanded is the price of the product.a. Quantity demanded is negatively related to price. This implies that the demand curve isdownward sloping.b. Definition of law of demand: the claim that, other things being equal, thequantity demanded of a good falls when the price of the good rises .3. Definition of demand schedule: a table that shows the relationship between theprice of a good and the quantity demanded. Price of Ice-Cream ConeQuantity of Cones Demanded$0.0012 $0.5010 $1.008 $1.506 $2.004 $2.502 $3.00Figure 1Make sure that you explain that, when we discuss the relationship between quantity demanded and price, we hold all other variables constant. You will need toemphasize this more than once to ensure that students understand why a change inprice leads to a movement along the demand curve.Chapter 4/The Market Forces of Supply and Demand ❖ 554. Definition of demand curve: a graph of the relationship between the price of a good and the quantity demanded.a. Price is generally drawn on the vertical axis.b. Quantity demanded is represented on the horizontal axis. B. Market Demand versus Individual Demand1. The market demand is the sum of all of the individual demands for a particular good orservice.2. The demand curves are summed horizontally —meaning that the quantities demanded are added up for each level of price.3. The market demand curve shows how the total quantity demanded of a good varies with the price of the good, holding constant all other factors that affect how much consumers want to buy.C. Shifts in the Demand Curve1. Because the market demand curve holds other things constant, it need not be stable overtime.56 ❖ Chapter 4/The Market Forces of Supply and Demand2. If any of these other factors change, the demand curve will shift.a. An increase in demand is represented by a shift of the demand curve to the right.b. A decrease in demand is represented by a shift of the demand curve to the left.3. Incomea. The relationship between income and quantity demanded depends on what type of good the product is.b. Definition of normal good: a good for which, other things equal, an increase in income leads to an increase in demand.c. Definition of inferior good: a good for which, other things equal, an increase inincome leads to a decrease in demand.4. Prices of Related Goodsa. Definition of substitutes: two goods for which an increase in the price of one good leads to an increase in the demand for the other.b. Definition of complements: two goods for which an increase in the price of one good leads to a decrease in the demand for the other.5. Tastes6. Expectationsa. Future incomeb. Future prices7. Number of BuyersChapter 4/The Market Forces of Supply and Demand ❖57D. Case Study: Two Ways to Reduce the Quantity of Smoking Demanded1. Public service announcements, mandatory health warnings on cigarette packages, and theprohibition of cigarette advertising on television are policies designed to reduce the demandfor cigarettes (and shift the demand curve to the left).2. Raising the price of cigarettes (through tobacco taxes) lowers the quantity of cigarettesdemanded.a. The demand curve does not shift in this case, however.b. An increase in the price of cigarettes can be shown by a movement along the originaldemand curve.3. Studies have shown that a 10% increase in the price of cigarettes causes a 4% reduction inthe quantity of cigarettes demanded. For teens, a 10% increase in price leads to a 12% dropin quantity demanded.4. Studies have also shown that a decrease in the price of cigarettes is associated with greateruse of marijuana. Thus, it appears that tobacco and marijuana are complements.III. SupplyA. The Supply Curve: The Relationship between Price and Quantity Supplied1. Definition of quantity supplied: the amount of a good that sellers are willing andable to sell.a. Quantity supplied is positively related to price. This implies that the supply curve will beupward sloping.b. Definition of law of supply: the claim that, other things equal, the quantitysupplied of a good rises when the price of the good rises.2. Definition of supply schedule: a table that shows the relationship between the priceof a good and the quantity supplied.58 ❖ Chapter 4/The Market Forces of Supply and Demand3. Definition of supply curve: a graph of the relationship between the price of a good and the quantity supplied. Price of Ice-Cream ConeQuantity of Cones Supplied$0.000 $0.50 0 $1.001 $1.502 $2.003 $2.504 $3.005B. Market Supply versus Individual Supply1. The market supply curve can be found by summing individual supply curves.2. Individual supply curves are summed horizontally at every price.3. The market supply curve shows how the total quantity supplied varies as the price of thegood varies.C. Shifts in the Supply Curve1. Because the market supply curve holds other things constant, the supply curve will shift ifany of these factors changes.a. An increase in supply is represented by a shift of the supply curve to the right.b. A decrease in supply is represented by a shift of the supply curve to the left.Figure 5Figure 7Figure 6You will want to take time to emphasize the difference between a “change in supply” and a “change in quantity supplied.”Chapter 4/The Market Forces of Supply and Demand ❖ 592. Input Prices3. Technology4. Expectations5. Number of Sellers IV. Supply and Demand TogetherA. Equilibrium1. The point where the supply and demand curves intersect is called the market’s equilibrium.2. Definition of equilibrium: a situation in which the market price has reached thelevel at which quantity supplied equals quantity demanded.3. Definition of equilibrium price: the price that balances quantity supplied andquantity demanded.4. The equilibrium price is often called the "market-clearing" price because both buyers andsellers are satisfied at this price.Table 2Figure 8 Students will benefit from seeing equilibrium using both a graph and a supply-and-demand schedule. The schedule will also make it easier for students to understand concepts such as shortages and surpluses.60 ❖Chapter 4/The Market Forces of Supply and Demand5. Definition of equilibrium quantity: the quantity supplied and the quantitydemanded at the equilibrium price.6. If the actual market price is higher than the equilibrium price, there will be a surplus of thegood.Figure 9a. Definition of surplus: a situation in which quantity supplied is greater thanquantity demanded.b. To eliminate the surplus, producers will lower the price until the market reachesequilibrium.7. If the actual price is lower than the equilibrium price, there will be a shortage of the good.a. Definition of shortage: a situation in which quantity demanded is greater thanquantity supplied.b. Sellers will respond to the shortage by raising the price of the good until the marketreaches equilibrium.8. Definition of the law of supply and demand: the claim that the price of any goodadjusts to bring the supply and demand for that good into balance.B. Three Steps to Analyzing Changes in Equilibrium 1. Decide whether the event shifts the supply or demand curve (or perhaps both). 2. Determine the direction in which the curve shifts.3. Use the supply-and-demand diagram to see how the shift changes the equilibrium price andquantity. C. Example: A change in market equilibrium due to a shift in demand —the effect of hot weather onthe market for ice cream.D. Shifts in Curves versus Movements along Curves1. A shift in the demand curve is called a "change in demand." A shift in the supply curve iscalled a "change in supply."2. A movement along a fixed demand curve is called a "change in quantity demanded." Amovement along a fixed supply curve is called a "change in quantity supplied." E. Example: A change in market equilibrium due to a shift in supply —the effect of a hurricane thatdestroys part of the sugar-cane crop and drives up the price of sugar.F. Example: Shifts in both supply and demand —the effect of hot weather and a hurricane thatdestroys part of the sugar cane crop. G. Summary1. When an event shifts the supply or demand curve, we can examine the effects on theequilibrium price and quantity.ALTERNATIVE CLASSROOM EXAMPLE:Go through these examples of events that would shift either the demand or supply of #2 lead pencils:▪ an increase in the income of consumers▪ an increase in the use of standardized exams (using opscan forms) ▪ a decrease in the price of graphite (used in the production of pencils) ▪ a decrease in the price of ink pens ▪ the start of a school year▪ new technology that lowers the cost of producing pencils.2. Table 4 reports the end results of these shifts in supply and demand.H. In the News: Price Increases after Disasters1. When a disaster strikes a region, many good experience an increase in demand or a decreasein supply resulting in upward pressure on prices.2. This article from defends price increases following natural disasters as a naturalresult of market interactions.V. Conclusion: How Prices Allocate ResourcesA. The model of supply and demand is a powerful tool for analyzing markets.B. Supply and demand together determine the prices of the economy’s goods and services.1. These prices serve as signals that guide the allocation of scarce resources in the economy.2. Prices determine who produces each good and how much of each good is produced.SOLUTIONS TO TEXT PROBLEMS:Quick Quizzes1. A market is a group of buyers (who determine demand) and a group of sellers (whodetermine supply) of a particular good or service. A perfectly competitive market is one inwhich there are many buyers and many sellers of an identical product so that each has anegligible impact on the market price.2. Here is an example of a monthly demand schedule for pizza:Price of Pizza Slice Number of Pizza Slices Demanded$ 0.00 100.25 90.50 80.75 71.00 61.25 51.50 41.75 32.00 22.25 12.50 0The demand curve is graphed in Figure 1.Figure 1Examples of things that would shift the demand curve include changes in income, prices ofrelated goods like soda or hot dogs, tastes, expectations about future income or prices, andthe number of buyers.A change in the price of pizza would not shift this demand curve; it would only lead to amovement from one point to another along the same demand curve.3. Here is an example of a monthly supply schedule for pizza:Price of Pizza Slice Number of PizzaSlices Supplied$ 0.00 00.25 1000.50 2000.75 3001.00 4001.25 5001.50 6001.75 7002.00 8002.25 9002.50 1000The supply curve is graphed in Figure 2.Figure 2Figure 3Examples of things that would shift the supply curve include changes in prices of inputs like tomato sauce and cheese, changes in technology like more efficient pizza ovens or automatic dough makers, changes in expectations about the future price of pizza, or a change in the number of sellers.A change in the price of pizza would not shift this supply curve; it would only lead to amovement from one point to another along the same supply curve.4. If the price of tomatoes rises, the supply curve for pizza shifts to the left because there hasbeen an increase in the price of an input into pizza production, but there is no shift indemand. The shift to the left of the supply curve causes the equilibrium price to rise and the equilibrium quantity to decline, as Figure 3 shows.If the price of hamburgers falls, the demand curve for pizza shifts to the left because thelower price of hamburgers will lead consumers to buy more hamburgers and fewer pizzas,but there is no shift in supply. The shift to the left of the demand curve causes theequilibrium price to fall and the equilibrium quantity to decline, as Figure 4 shows.Figure 4Questions for Review1. A competitive market is a market in which there are many buyers and many sellers of anidentical product so that each has a negligible impact on the market price. Another type ofmarket is a monopoly, in which there is only one seller. There are also other markets that fallbetween perfect competition and monopoly.2. The demand schedule is a table that shows the relationship between the price of a good andthe quantity demanded. The demand curve is the downward-sloping line relating price andquantity demanded. The demand schedule and demand curve are related because thedemand curve is simply a graph showing the points in the demand schedule.The demand curve slopes downward because of the law of demand—other things beingequal, when the price of a good rises, the quantity demanded of the good falls. People buyless of a good when its price rises, both because they cannot afford to buy as much andbecause they switch to purchasing other goods.3. A change in consumers' tastes leads to a shift of the demand curve. If the change inconsumers' tastes leads to an increase in demand, consumers want to buy more of this goodat every price level. A change in price leads to a movement along the demand curve.Because price is measured on the vertical axis, a change in the price represents a movementalong the demand curve.4. Because Popeye buys more spinach when his income falls, spinach is an inferior good for him.His demand curve for spinach shifts out to the right as a result of the decrease in his income.5. A supply schedule is a table showing the relationship between the price of a good and thequantity a producer is willing and able to supply. The supply curve is the upward-sloping linerelating price and quantity supplied. The supply schedule and the supply curve are related because the supply curve is simply a graph showing the points in the supply schedule.The supply curve slopes upward because when the price is high, suppliers' profits increase, so they supply more output to the market. The result is the law of supply—other things being equal, when the price of a good rises, the quantity supplied of the good also rises.6. A change in producers' technology leads to a shift in the supply curve. A change in priceleads to a movement along the supply curve.7. The equilibrium of a market is the point at which the quantity demanded is equal to quantitysupplied. If the price is above the equilibrium price, sellers want to sell more than buyers want to buy, so there is a surplus. Sellers try to increase their sales by cutting prices. That continues until they reach the equilibrium price. If the price is below the equilibrium price, buyers want to buy more than sellers want to sell, so there is a shortage. Sellers can raise their price without losing customers. That continues until they reach the equilibrium price.8. When the price of beer rises, the demand for pizza declines, because beer and pizza arecomplements and people want to buy less beer. When we say the demand for pizza declines, we mean that the demand curve for pizza shifts to the left as in Figure 5. The supply curve for pizza is not affected. With a shift to the left in the demand curve, the equilibrium price and quantity both decline, as the figure shows. Thus, the quantity of pizza supplied anddemanded both fall. In sum, supply is unchanged, demand is decreased, quantity supplied declines, quantity demanded declines, and the price falls.Figure 59. Prices play a vital role in market economies because they bring markets into equilibrium. Ifthe price is different from its equilibrium level, quantity supplied and quantity demanded are not equal. The resulting surplus or shortage leads suppliers to adjust the price untilequilibrium is restored. Prices thus serve as signals that guide economic decisions andallocate scarce resources.Quick Check Multiple Choice1. b2. b3. d4. b5. a6. cProblems and Applications1. a. Cold weather damages the orange crop, reducing the supply of oranges and raising theprice of oranges. This leads to a decline in the supply of orange juice because orangesare an important input in the production of orange juice. This can be seen in Figure 6 asa shift to the left in the supply curve for orange juice. The new equilibrium price is higherthan the old equilibrium price.Figure 6b. People often travel to the Caribbean from New England to escape cold weather, so thedemand for Caribbean hotel rooms is high in the winter. In the summer, fewer peopletravel to the Caribbean, because northern climates are more pleasant. The result, asshown in Figure 7, is a shift to the left in the demand curve. The equilibrium price ofCaribbean hotel rooms is thus lower in the summer than in the winter, as the figureshows.Figure 7c. When a war breaks out in the Middle East, many markets are affected. Because a largeproportion of oil production takes place there, the war disrupts oil supplies, shifting thesupply curve for gasoline to the left, as shown in Figure 8. The result is a rise in theequilibrium price of gasoline. With a higher price for gasoline, the cost of operating agas-guzzling automobile like a Cadillac will increase. As a result, the demand for usedCadillacs will decline, as people in the market for cars will not find Cadillacs as attractive.In addition, some people who already own Cadillacs will try to sell them. The result isthat the demand curve for used Cadillacs shifts to the left, while the supply curve shifts to the right, as shown in Figure 9. The result is a decline in the equilibrium price of used Cadillacs.Figure 8 Figure 92. The statement is false. As Figure 10 shows, in equilibrium the increase in demand fornotebooks results in an increased quantity demanded and the quantity supplied.Figure 10 Figure 113. a. If people decide to have more children, they will want larger vehicles for hauling theirkids around, so the demand for minivans will increase. Supply will not be affected. The result is a rise in both the price and the quantity sold, as Figure 12 shows.Figure 12 Figure 13b. If a strike by steelworkers raises steel prices, the cost of producing a minivan rises andthe supply of minivans decreases. Demand will not be affected. The result is a rise in the price of minivans and a decline in the quantity sold, as Figure 13 shows.c. The development of new automated machinery for the production of minivans is animprovement in technology. This reduction in firms' costs will result in an increase in supply. Demand is not affected. The result is a decline in the price of minivans and an increase in the quantity sold, as Figure 14 shows.Figure 14d. The rise in the price of sport utility vehicles affects minivan demand because sport utilityvehicles are substitutes for minivans. The result is an increase in demand for minivans.Supply is not affected. The equilibrium price and quantity of minivans both rise, as Figure12 shows.e. The reduction in peoples' wealth caused by a stock-market crash reduces their income,leading to a reduction in the demand for minivans, because minivans are likely a normal good. Supply is not affected. As a result, both the equilibrium price and the equilibrium quantity decline, as Figure 15 shows.Figure 154. a. DVDs and TV screens are likely to be complements because you cannot watch a DVDwithout a television. DVDs and movie tickets are likely to be substitutes because a movie can be watched at a theater or at home. TV screens and movie tickets are likely to besubstitutes for the same reason.b. The technological improvement would reduce the cost of producing a TV screen, shiftingthe supply curve to the right. The demand curve would not be affected. The result is that the equilibrium price will fall, while the equilibrium quantity will rise. This is shown inFigure 16.Figure 16c. The reduction in the price of TV screens would lead to an increase in the demand forDVDs because TV screens and DVDs are complements. The effect of this increase in the demand for DVDs is an increase in both the equilibrium price and quantity, as shown inFigure 17.Figure 17The reduction in the price of TV screens would cause a decline in the demand for movie tickets because TV screens and movie tickets are substitute goods. The decline in thedemand for movie tickets would lead to a decline in the equilibrium price and quantitysold. This is shown in Figure 18.Figure 185. Technological advances that reduce the cost of producing computer chips represent a declinein an input price for producing a computer. The result is a shift to the right in the supply of computers, as shown in Figure 19. The equilibrium price falls and the equilibrium quantity rises, as the figure shows.Figure 19Because computer software is a complement to computers, the lower equilibrium price of computers increases the demand for software. As Figure 20 shows, the result is a rise in both the equilibrium price and quantity of software.Figure 20Because typewriters are substitutes for computers, the lower equilibrium price of computers reduces the demand for typewriters. As Figure 21 shows, the result is a decline in both the equilibrium price and quantity of typewriters.Figure 216. a. When a hurricane in South Carolina damages the cotton crop, it raises input prices forproducing sweatshirts. As a result, the supply of sweatshirts shifts to the left, as shownin Figure 22. The new equilibrium price is higher and the new equilibrium quantity ofsweatshirts is lower.。

曼昆宏观经济学最新英文版参考答案第34章

曼昆宏观经济学最新英⽂版参考答案第34章Chapter 34Problems and Applicat ions1. a. When the Fed’s bond traders buy bonds in open-market operations, themoney-supply curve shifts to the right from MS1 to MS2, as shown in Figure 1.The result is a decline in the interest rate.Figure 1Figure 2b. When an increase in credit card availability reduces the cash people hold, themoney-demand curve shifts to the left from MD1 to MD2, as shown in Figure 2.The result is a decline in the interest rate.c. When the Federal Reserve reduces reserve requirements, the money supply increases, so the money-supply curve shifts to the right from MS1 to MS2, asshown in Figure 1. The result is a decline in the interest rate.d. When households decide to hold more money to use for holiday shopping, themoney-demand curve shifts to the right from MD1 to MD2, as shown in Figure3. The result is a rise in the interest rate.Figure 3e. When a wave of optimism boosts business investment and expands aggregatedemand, money demand increases from MD1 to MD2 in Figure 3. The increase in money demand increases the interest rate.Figure 42. a. The increase in the money supply will cause the equilibrium interest rate todecline, as shown in Figure 4. Households will increase spending and willinvest in more new housing. Firms too will increase investment spending. Thiswill cause the aggregate demand curve to shift to the right as shown in Figure5.Figure 5b. As shown in Figure 5, the increase in aggregate demand will cause an increase in both output and the price level in the short run.c. When the economy makes the transition from its short-run equilibrium to its long-run equilibrium, short-run aggregate supply will decline, causing the price level to rise even further.d. The increase in the price level will cause an increase in the demand for money, raising the equilibrium interest rate.e. Yes. While output initially rises because of the increase in aggregate demand, it will fall once short-run aggregate supply declines. Thus, there is no long-run effect of the increase in the money supply on real output.Figure 63. a. When more ATMs are available, money demand is reduced and themoney-demand curve shifts to the left from MD1 to MD2, as shown in Figure 6.If the Fed does not change the money supply, which is at MS1, the interest rate will decline from r1 to r2. The decline in the interest rate shifts theaggregate-demand curve to the right, as consumption and investment increase.b. If the Fed wants to stabilize aggregate demand, it should reduce the money supply to MS2, so the interest rate will remain at r1 and aggregate demand will not change.4. A tax cut that is permanent will have a bigger impact on consumer spending and aggregate demand. If the tax cut is permanent, consumers will view it as addingsubstantially to their financial resources, and they will increase their spendingsubstantially. If the tax cut is temporary, consumers will view it as adding just a little to their financial resources, so they will not increase spending as much.5. a. The current situation is shown in Figure 7.Figure 7b. The Fed will want to stimulate aggregate demand. Thus, it will need to lowerthe interest rate by increasing the money supply. This could be achieved if the Fed purchases government bonds from the public.Figure 8c. As shown in Figure 8, the Fed's purchase of government bonds shifts thesupply of money to the right, lowering the interest rate.d. The Fed's purchase of government bonds will increase aggregate demand asconsumers and firms respond to lower interest rates. Output and the pricelevel will rise as shown in Figure 9.Figure 96. a. Legislation allowing banks to pay interest on checking deposits increases the return to money relative to other financial assets, thus increasing money demand.b. If the money supply remained constant (at MS1), the increase in the demand for money would have raised the interest rate, as shown in Figure 10. The risein the interest rate would have reduced consumption and investment, thus reducing aggregate demand and output.c. To maintain a constant interest rate, the Fed would need to increase the money supply from MS1 to MS2. Then aggregate demand and output would be unaffected.Figure 107. a. If there is no crowding out, then the multiplier equals 1/(1 –MPC). Because the multiplier is 3, then MPC = 2/3.b. If there is crowding out, then the MPC would be larger than 2/3. An MPC that is larger than 2/3 would lead to a larger multiplier than 3, which is then reduced down to 3 by the crowding-out effect.8. a. The initial effect of the tax reduction of $20 billion is to increase aggregatedemand by $20 billion x 3/4 (the MPC) = $15 billion.b. Additional effects follow this initial effect as the added incomes are spent. Thesecond round leads to increased consumption spending of $15 billion x 3/4 =$11.25 billion. The third round gives an increase in consumption of $11.25billion x 3/4 = $8.44 billion. The effects continue indefinitely. Adding them allup gives a total effect that depends on the multiplier. With an MPC of 3/4, themultiplier is 1/(1 – 3/4) = 4. So the total effect is $15 billion x 4 = $60 billion.c. Government purchases have an initial effect of the full $20 billion, becausethey increase aggregate demand directly by that amount. The to tal effect of anincrease in government purchases is thus $20 billion x 4 = $80 billion. Sogovernment purchases lead to a bigger effect on output than a tax cut does.The difference arises because government purchases affect aggregatedemand by the full amount, but a tax cut is partly saved by consumers, andtherefore does not lead to as much of an increase in aggregate demand.9. If government spending increases, aggregate demand rises, so money demand rises.The increase in money demand leads to a rise in the interest rate and thus a decline in aggregate demand if the Fed does not respond. But if the Fed maintains a fixed interest rate, it will increase money supply, so aggregate demand will not decline. Thus, theeffect on aggregate demand from an increase in government spending will be larger if the Fed maintains a fixed interest rate.10. a. Expansionary fiscal policy is more likely to lead to a short-run increase ininvestment if the investment accelerator is large. A large investmentaccelerator means that the increase in output caused by expansionary fiscalpolicy will induce a large increase in investment. Without a large accelerator,investment might decline because the increase in aggregate demand will raisethe interest rate.b. Expansionary fiscal policy is more likely to lead to a short-run increase ininvestment if the interest sensitivity of investment is small. Because fiscalpolicy increases aggregate demand, thus increasing money demand and theinterest rate, the greater the sensitivity of investment to the interest rate thegreater the decline in investment will be, which will offset the positiveaccelerator effect.11. a. Tax revenue declines when the economy goes into a recession because taxesare closely related to economic activity. In a recession, people's incomes andwages fall, as do firms' profits, so taxes on these things decline.b. Government spending rises when the economy goes into a recession becausemore people get unemployment-insurance benefits, welfare benefits, andother forms of income support.c. If the government were to operate under a strict balanced-budget rule, it would have to raise tax rates or cut government spending in a recession. Both would reduce aggregate demand, making the recession more severe.12. a. If there were a contraction in aggregate demand, the Fed would need to increase the money supply to increase aggregate demand and stabilize the price level, as shown in Figure 11. By increasing the money supply, the Fed is able to shift the aggregate-demand curve back to AD1 from AD2. This policy stabilizes output and the price level.Figure 11b. If there were an adverse shift in short-run aggregate supply, the Fed would need to decrease the money supply to stabilize the price level, shifting the aggregate-demand curve to the left from AD1 to AD2, as shown in Figure 12. This worsens the recession caused by the shift in aggregate supply. To stabilize output, the Fed would need to increase the money supply, shifting the aggregate-demand curve from AD1 to AD3. However, this action would raise the price level.。

曼昆经济学原理第五版课后练习答案

曼昆经济学原理第五版课后练习答案第一篇：曼昆经济学原理第五版课后练习答案第一篇导言第一章经济学十大原理1．列举三个你在生活中面临的重要权衡取合的例子。

答：①大学毕业后．面临着是否继续深造的选择，选择继续上学攻读研究生学位，就意味着在今后三年中放弃参加工作、赚工资和积累社会经验的机会；2、在学习内容上也面临着很重要的权衡取舍，如果学习《经济学》，就要减少学习英语或其他专业课的时间，③对于不多的生活费的分配同样面临权衡取舍，要多买书．就要减少在吃饭、买衣服等其他方面的开支。

2、看一场电影的机会成本是什么?答：看一场电影的机会成本是在看电影的时间里做其他事情所能获得的最大收益，例如：看书、打零工。

3、水是生活必需的。

一杯水的边际利益是大还是小呢?答：这要看这杯水是在什么样的情况下喝．如果这是一个人五分钟内喝下的第五杯水．那么他的边际利益很小．有可能为负；如果这是一个极度干渴的人喝下的第一杯水，那么他的边际利益将会极大。

4、为什么决策者应该考虑激励? 答：因为人们会对激励做出反应。

如果政策改变了激励，它将使人们改变自己的行为，当决策者未能考虑到行为如何由于政策的原因而变化时．他们的政策往往会产生意想不到的效果。

为什么各国之间的贸易不像竞赛一样有赢家和输家呢? 答：因为贸易使各国可以专门从事自己最擅长的话动，并从中享有更多的各种各样的物品与劳务。

通过贸易使每个国家可供消费的物质财富增加，经济状况变得更好。

因此，各个贸易国之间既是竞争对手，又是经济合作伙伴。

在公平的贸易中是“双赢”或者“多赢”的结果。

6．市场巾的那只“看不见的手”在做什么呢，答：市场中那只“看不见的手”就是商品价格，价格反映商品自身的价值和社会成本，市场中的企业和家庭在作出买卖决策时都要关注价格。

因此．他们也会不自觉地考虑自己行为的(社会)收益和成本。

从而，这只“看不见的手”指引着干百万个体决策者在大多数情况下使社会福利趋向最大化。

解释市场失灵的两个主要原因，并各举出一个例子。

曼昆经济学原理课件(下)-宏观部分，北大课件Chapter_34_货币和财政政策对总需求的影响

5
流动性偏好理论 The Theory of Liquidity Preference
凯恩斯发展了流动性偏好理论，以解释决定经济的利率的因素。 Keynes developed the theory of liquidity preference in order to explain what factors determine the economy’s interest rate. 按照这一理论，利率调整以平衡货币供求。 According to the theory, the interest rate adjusts to balance the supply and demand for money.
6
货币供给 Money Supply
货币供给由中央银行（美国的Fed）通过以下途径进行控制： The money supply is controlled by the Fed through:
公开市场运作 Open-market operations 改变法定准备金 Changing the reserve requirements 改变贴现率 Changing the discount rate
Aggregate demand
0
Quantity fixed by the Fed
Quantity of Money
0
Y2
3. …提高了均衡利率 which increases the equilibrium interest rate…
4. …这又减少了物品与服务的需求量 which in turn reduces the quantity of goods and services demanded.
第三十四章

经济学原理曼昆课后答案 chapter 3

Problems and Applicat ions1. In the text example of the farmer and the rancher, the farmer’s opportunity cost ofproducing one pound of meat is two pounds of potatoes because for every 20 hours of work, he can produce one pound of meat or two pounds of po tatoes. With limitedtime at his disposal, producing a pound of meat means he gives up the opportunity to produce two pounds of potatoes. Similarly, the rancher’s opportunity cost ofproducing one pound of meat is 1/8 pound of potatoes because for every hour of work, she can produce one pound of meat or 1/8 pound of potatoes. With limited time ather disposal, producing a pound of meat means she gives up the opportunity toproduce 1/8 pound of potatoes.2. a. See Figure 3-2. If Maria spends all five hours studying economics, she canread 100 pages, so that is the vertical intercept of the production possibilitiesfrontier. If she spends all five hours studying sociology, she can read 250pages, so that is the horizontal intercept. The time costs are constant, so theproduction possibilities frontier is a straight line.Figure 3-2b. It takes Maria two hours to read 100 pages of sociology. In that time, shecould read 40 pages of economics. So the opportunity cost of 100 pages ofsociology is 40 pages of economics.3. a.b. See Figure 3-3. With 100 million workers and four cars per worker, if eithereconomy were devoted completely to cars, it could make 400 million cars.Since a U.S. worker can produce 10 tons of grain, if the U.S. produced onlygrain it would produce 1,000 million tons. Since a Japanese worker canproduce 5 tons of grain, if Japan produced only grain it would produce 500million tons. These are the intercepts of the production possibilities frontiers shown in the figure. Note that since the tradeoff between cars and grain isconstant, the production possibilities frontier is a straight line.Figure 3-3c. Since a U.S. worker produces either 4 cars or 10 tons of grain, the opportunitycost of 1 car is 2½ tons of grain, which is 10 divided by 4. Since a Japanese worker produces either 4 cars or 5 tons of grain, the opportunity cost of 1 car is1 1/4 tons of grain, which is 5 divided by 4. Similarly, the U.S. opportunitycost of 1 ton of grain is 2/5 cars (4 divided by 10) and the Japaneseopportunity cost of 1 ton of grain is 4/5 cars (4 divided by 5). This gives the following table:d. Neither country has an absolute advantage in producing cars, since they’reequally productive (the same output per worker); the U.S. has an absoluteadvantag e in producing grain, since it’s more productive (greater output perworker).e. Japan has a comparative advantage in producing cars, since it has a loweropportunity cost in terms of grain given up. The U.S. has a comparativeadvantage in producing grain, since it has a lower opportunity cost in terms ofcars given up.f. With half the workers in each country producing each of the goods, the U.S.would produce 200 million cars (that’s 50 million workers times 4 cars each)and 500 million tons of grain (50 million workers times 10 tons each). Japanwould produce 200 million cars (50 million workers times 4 cars each) and 250million tons of grain (50 million workers times 5 tons each).g. From any situation with no trade, in which each country is producing some carsand some grain, suppose the U.S. changed 1 worker from producing cars toproducing grain. That worker would produce 4 fewer cars and 10 additionaltons of grain. Then suppose the U.S. offers to trade 7 tons of grain to Japanfor 4 cars. The U.S. will do this because it values 4 cars at 10 tons of grain, soit will be better off if the trade goes through. Suppose Japan changes 1worker from producing grain to producing cars. That worker would produce 4more cars and 5 fewer tons of grain. Japan will take the trade because itvalues 4 cars at 5 tons of grain, so it will be better off. With the trade and thechange of 1 worker in both the U.S. and Japan, each country gets the sameamount of cars as before and both get additional tons of grain (3 for the U.S.and 2 for Japan). Thus by trading and changing their production, bothcountries are better off.4. a. Pat’s opportunity cost of making a pizza is 1/2 gallon of root beer, since shecould brew 1/2 gallon in the time (2 hours) it takes her to make a pizza. Pathas an absolute advantage in making pizza since she can make one in twohours, while it takes Kris four hours. Kris’s opportunity cost of making a pizzais 2/3 gallons of root beer, since she could brew 2/3 of a gallon in the time (4hours) it takes her to make a pizza. Since Pat’s opportunity cost of makingpizza is less than Kris’s, Pat has a comparative advantage in making pizza.b. Since Pat has a comparative advantage in making pizza, she will make pizzaand exchange it for root beer that Kris makes.c. The highest price of pizza in terms of root beer that will make both roommatesbetter off is 2/3 gallons of root beer. If the price were higher than that, thenKris would prefer making her own pizza (at an opportunity cost of 2/3 gallonsof root beer) rather than trading for pizza that Pat makes. The lowest price ofpizza in terms of root beer that will make both roommates better off is 1/2gallon of root beer. If the price were lower than that, then Pat would prefermaking her own root beer (she can make 1/2 gallon of root beer instead ofmaking a pizza) rather than trading for root beer that Kris makes.5. a. Since a Canadian worker can make either two cars a year or 30 bushels ofwheat, the opportunity cost of a car is 15 bushels of wheat. Similarly, theopportunity cost of a bushel of wheat is 1/15 of a car. The opportunity costsare the reciprocals of each other.b. See Figure 3-4. If all 10 million workers produce two cars each, they producea total of 20 million cars, which is the vertical intercept of the productionpossibilities frontier. If all 10 million workers produce 30 bushels of wheateach, they produce a total of 300 million bushels, which is the horizontalintercept of the production possibilities frontier. Since the tradeoff betweencars and wheat is always the same, the production possibilities frontier is astraight line.If Canada chooses to consume 10 million cars, it will need 5 million workersdevoted to car production. That leaves 5 million workers to produce wheat,who will produce a total of 150 million bushels (5 million workers times 30bushels per worker). This is shown as point A on Figure 3-4.c. If the United States buys 10 million cars from Canada and Canada continues toconsume 10 million cars, then Canada will need to produce a total of 20 millioncars. So Canada will be producing at the vertical intercept of the productionpossibilities frontier. But if Canada gets 20 bushels of wheat per car, it will beable to consume 200 million bushels of wheat, along with the 10 million cars.This is shown as point B in the figure. Canada should accept the deal becauseit gets the same number of cars and 50 million more bushes of wheat.Figure 3-46. Though the professor could do both writing and data collection faster than the student(that is, he has an absolute advantage in both), his time is limited. If the professor’s comparative advantage is in writing, it makes sense for him to pay a student to collect the data, since that’s the student’s comparative advantage.7. a. English workers have an absolute advantage over Scottish workers inproducing scones, since English workers produce more scones per hour (50 vs.40). Scottish workers have an absolute advantage over English workers inproducing sweaters, since Scottish workers produce more sweaters per hour(2 vs. 1). Comparative advantage runs the same way. English workers, whohave an opportunity cost of 1/50 sweaters per scone (1 sweater per hourdivided by 50 scones per hour), have a comparative advantage in sconeproduction over Scottish workers, who have an opportunity cost of 1/20sweater per scone (2 sweaters per hour divided by 40 scones per hour).Scottish workers, who have an opportunity cost of 20 scones per sweater (40scones per hour divided by 2 sweaters per hour), have a comparativeadvantage in sweater production over English workers, who have anopportunity cost of 50 scones per sweater (50 scones per hour divided by 1sweater per hour).b. If England and Scotland decide to trade, Scotland will produce sweaters andtrade them for scones produced in England. A trade with a price between 20and 50 scones per sweater will benefit both countries, as they’ll be getting thetraded good at a lower price than their opportunity cost of producing the goodin their own country.c. Even if a Scottish worker produced just one sweater per hour, the countrieswould still gain from trade, because Scotland would still have a comparativeadvantage in producing sweaters. Its opportunity cost for sweaters would behigher than before (40 scones per sweater, instead of 20 scones per sweaterbefore). But there are still gains from trade since England has a higheropportunity cost (50 scones per sweater).8. a. Technological advance lowers the opportunity cost of producing meat for thefarmer. The opportunity cost of producing a point of meat was 2 pounds ofpotatoes; it’s now 1/5 pounds of potatoes. Thus the farmer’s opportunitycost of producing potatoes is now 5 pounds of meat. Si nce the rancher’sopportunity cost of producing potatoes is 8 pounds of meat, the farmer still hasa comparative advantage in producing potatoes and the rancher still has acomparative advantage in producing meat.b. Now the farmer won’t be willing to tr ade a pound of potatoes for 3 pounds ofmeat because if he produced one less pound of potatoes, he could produce 5more pounds of meat. So the trade would be bad for the farmer, as he wouldthen be consuming inside his production possibilities frontier.c. The farmer and rancher would now be willing to trade one pound of potatoesfor an amount between 5 and 8 pounds of meat, with the potatoes beingproduced by the farmer and the meat being produced by the rancher.9. a. With no trade, one pair of white socks trades for one pair of red socks inBoston, since productivity is the same for the two types of socks. The price inChicago is 2 pairs of red socks per pair of white socks.b. Boston has an absolute advantage in the production of both types of socks,since a worker in Boston produces more (3 pairs of socks per hour) than aworker in Chicago (2 pairs of red socks per hour or 1 pair of white socks perhour).Chicago has a comparative advantage in producing red socks, since theopportunity cost of producing a pair of red socks in Chicago is 1/2 pair of whitesocks, while the opportunity cost of producing a pair of red socks in Boston is 1pair of white socks. Boston has a comparative advantage in producing whitesocks, since the opportunity cost of producing a pair of white socks in Boston is1 pair of red socks, while the opportunity cost of producing a pair of whitesocks in Chicago is 2 pairs of red socks.c. If they trade socks, Boston will produce white socks for export, since it has thecomparative advantage in white socks, while Chicago produces red socks forexport, which is Chicago’s comparative advantage.d. Trade can occur at any price between 1 and 2 pairs of red socks per pair ofwhite socks. At a price lower than 1 pair of red socks per pair of white socks,Boston will choose to produce its own red socks (at a cost of 1 pair of red socksper pair of white socks) instead of buying them from Chicago. At a pricehigher than 2 pairs of red socks per pair of white socks, Chicago will choose toproduce its own white socks (at a cost of 2 pairs of red socks per pair of whitesocks) instead of buying them from Boston.10. a. The cost of all goods is lower in Germany than in France in the sense that allgoods can be produced with fewer worker hours.b. The cost of any good for which France has a comparative advantage is lower inFrance than in Germany. Though Germany produces all goods with less labor,that labor is more valuable. So the cost of production, in terms of opportunitycost, will be lower in France for some goods.c. Trade between Germany and France will benefit both countries. For eachgood in which it has a comparative advantage, each country should producemore goods than it consumes, trading the rest to the other country. Totalconsumption will be higher in both countries as a result.11. a. True; two countries can achieve gains from trade even if one of the countrieshas an absolute advantage in the production of all goods. All that’s necessaryis that each country have a comparative advantage in some good.b. False; it is not true that some people have a comparative advantage ineverything they do. In fact, no one can have a comparative advantage ineverything. Comparative advantage reflects the opportunity cost of one goodor activity in terms of another. If you have a comparative advantage in onething, you must have a comparative disadvantage in the other thing.c. False; it is not true that if a trade is good for one person, it can’t be good forthe other one. Trades can and do benefit both sides especially trades basedon comparative advantage. If both sides didn’t benefit, trades would neveroccur.。

5学原理》（微观）第五版测试题库（04）曼昆经济学原理第五版测试题库（微观）

5学原理》（微观）第五版测试题库（04）曼昆经济学原理第五版测试题库（微观）Chapter 4The Market Forces of Supply and DemandTRUE/FALSE1. Prices allocate a market economy’s scarce resources.ANS: T DIF: 1 REF: 4-0NAT: Analytic LOC: Markets, market failure, and externalitiesTOP: Market economies MSC: Definitional2. In a market economy, supply and demand determine both the quantity of each good produced and the price atwhich it is sold.ANS: T DIF: 1 REF: 4-0NAT: Analytic LOC: Markets, market failure, and externalitiesTOP: Market economies MSC: Definitional3. A market is a group of buyers and sellers of a particular good or service.ANS: T DIF: 1 REF: 4-1NAT: Analytic LOC: Markets, market failure, and externalitiesTOP: Markets MSC: Definitional4. Sellers as a group determine the demand for a product, and buyers as a group determine the supply of aproduct.ANS: F DIF: 1 REF: 4-1NAT: Analytic LOC: Supply and demand TOP: Demand | SupplyMSC: Definitional5. A yard sale is an example of a market.ANS: T DIF: 2 REF: 4-1NAT: Analytic LOC: Markets, market failure, and externalitiesTOP: Markets MSC: Applicative6. A newspaper’s classified ads are an example of a market.ANS: T DIF: 2 REF: 4-1NAT: Analytic LOC: Markets, market failure, and externalitiesTOP: Markets MSC: Applicative7. Most markets in the economy are highly competitive.ANS: T DIF: 1 REF: 4-1NAT: Analytic LOC: Markets, market failure, and externalitiesTOP: Markets MSC: Definitional8. In a competitive market, the quantity of each good produced and the price at which it is sold are not determined by any single buyer or seller.ANS: T DIF: 1 REF: 4-1NAT: Analytic LOC: Markets, market failure, and externalitiesTOP: Competitive markets MSC: Definitional9. In a competitive market, there are so few buyers and so few sellers that each has a significant impact on the market price.ANS: F DIF: 1 REF: 4-1NAT: Analytic LOC: Markets, market failure, and externalitiesTOP: Competitive markets MSC: Definitional10. In a perfectly competitive market, the goods offered for sale are all exactly the same.ANS: T DIF: 1 REF: 4-1NAT: Analytic LOC: Perfect competition TOP: Perfect competitionMSC: Definitional20211. In a perfectly competitive market, buyers and sellers are price setters.ANS: F DIF: 1 REF: 4-1NAT: Analytic LOC: Perfect competition TOP: Perfect competitionMSC: Definitional12. All goods and services are sold in perfectly competitive markets.ANS: F DIF: 1 REF: 4-1NAT: Analytic LOC: Perfect competition TOP: Perfect competitionMSC: Definitional13. If a good or service has only one seller, then the seller is called a monopoly.ANS: T DIF: 1 REF: 4-1NAT: Analytic LOC: Monopoly TOP: Monopoly MSC: Definitional14. Monopolists are price takers.ANS: F DIF: 2 REF: 4-1NAT: Analytic LOC: Monopoly TOP: Monopoly MSC: Interpretive15. Local cable TV companies frequently are monopolists.ANS: T DIF: 1 REF: 4-1NAT: Analytic LOC: Monopoly TOP: Monopoly MSC: Definitional16. The quantity demanded of a product is the amount that buyers are willing and able to purchase at a particular price.ANS: T DIF: 1 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: Quantity demandedMSC: Definitional17. The law of demand is true for most goods in the economy.ANS: T DIF: 1 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: Law of demandMSC: Definitional18. The law of demand states that, other things equal, when the price of a good rises, the quantity demanded of the good rises, and when the price falls, the quantity demanded falls.ANS: F DIF: 1 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: Law of demandMSC: Definitional19. The demand curve is the upward-sloping line relating price and quantity demanded.ANS: F DIF: 1 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: Demand curveMSC: Definitional20. Individual demand curves are summed horizontally to obtain the market demand curve.ANS: T DIF: 1 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: Market demand curveMSC: Definitional21. The market demand curve shows how the total quantity demanded of a good varies as the income of buyers varies, while all the other factors that affect how much consumers want to buy are held constant.ANS: F DIF: 1 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: Market demand curveMSC: Definitional22. If something happens to alter the quantity demanded at any given price, then the demand curve shifts. ANS: T DIF: 1 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: Demand curveMSC: Definitionalword⽂档可⾃由复制编辑204 Chapter 4 /The Market Forces of Supply and Demand23. A movement upward and to the left along a given demand curve is called a decrease in demand..ANS: F DIF: 2 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: Demand curveMSC: Interpretive24. An increase in demand shifts the demand curve to the left.ANS: F DIF: 1 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: Demand curveMSC: Definitional25. If the demand for a good falls when income falls, then the good is called an inferior good.ANS: F DIF: 1 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: Normal goodsMSC: Definitional26. When Mario's income decreases, he buys more pasta. For Mario, pasta is a normal good.ANS: F DIF: 2 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: Inferior goodsMSC: Applicative27. A decrease in income will shift the demand curve for an inferior good to the right.ANS: T DIF: 2 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: Inferior goodsMSC: Interpretive28. An increase in the price of a substitute good will shift the demand curve for a good to the right.ANS: T DIF: 2 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: SubstitutesMSC: Interpretive29. Baseballs and baseball bats are substitute goods.ANS: F DIF: 2 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: ComplementsMSC: Applicative30. A decrease in the price of a complement will shift the demand curve for a good to the left.ANS: F DIF: 2 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: ComplementsMSC: Interpretive31. When an increase in the price of one good lowers the demand for another good, the two goods are called complements.ANS: T DIF: 1 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: ComplementsMSC: Definitional32. Cocoa and marshmallows are complements, so a decrease in the price of cocoa will cause an increase in the demand for marshmallows.MSC: Applicative33. If a pe rson expects the price of socks to increase next month, then that person’s current demand for socks will increase.ANS: T DIF: 2 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: ExpectationsMSC: Applicative34. A decrease in the price of a product and an increase in the number of buyers in the market affect the demandcurve in the same general way.ANS: F DIF: 2 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: Demand curveMSC: Interpretive35. Whenever a determinant of demand other than price changes, the demand curve shifts.ANS: T DIF: 2 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: Demand curveMSC: Interpretive36. An increase in the price of pizza will shift the demand curve for pizza to the left.ANS: F DIF: 2 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: Demand curveMSC: Applicative37. Public service announcements, mandatory health warnings on cigarette packages, and the prohibition ofcigarette advertising on television are all policies aimed at shifting the demand curve for cigarettes to the right. ANS: F DIF: 2 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: Demand curveMSC: Applicative38. Most studies have found that tobacco and marijuana are complements rather than substitutes.ANS: T DIF: 2 REF: 4-2NAT: Analytic LOC: Supply and demand TOP: ComplementsMSC: Applicative39. The quantity supplied of a good or service is the amount that sellers are willing and able to sell at a particularprice.ANS: T DIF: 1 REF: 4-3NAT: Analytic LOC: Supply and demand TOP: Quantity suppliedMSC: Definitional40. When the price of a good is high, selling the good is profitable, and so the quantity supplied is large.MSC: Definitional41. When the price of a good is low, selling the good is profitable, and so the quantity supplied is large. ANS: F DIF: 1 REF: 4-3NAT: Analytic LOC: Supply and demand TOP: Law of supplyMSC: Definitional42. Price cannot fall so low that some sellers choose to supply a quantity of zero.ANS: F DIF: 2 REF: 4-3NAT: Analytic LOC: Supply and demand TOP: Quantity suppliedMSC: Interpretive43. The law of supply states that, other things equal, when the price of a good rises, the quantity supplied of the good falls.ANS: F DIF: 1 REF: 4-3NAT: Analytic LOC: Supply and demand TOP: Law of supplyMSC: Definitional44. The law of supply states that, other things equal, when the price of a good falls, the quantity supplied falls as well.ANS: T DIF: 1 REF: 4-3NAT: Analytic LOC: Supply and demand TOP: Law of supplyMSC: Definitionalword⽂档可⾃由复制编辑206 Chapter 4 /The Market Forces of Supply and Demand45. If a higher price means a greater quantity supplied, then the supply curve slopes upward.ANS: T DIF: 1 REF: 4-3NAT: Analytic LOC: Supply and demand TOP: Supply curveMSC: Definitional46. Individual supply curves are summed vertically to obtain the market supply curve.ANS: F DIF: 1 REF: 4-3NAT: Analytic LOC: Supply and demand TOP: Market supply curveMSC: Definitional47. The market supply curve shows how the total quantity supplied of a good varies as input prices vary, holding constant all the other factors that influence producers’ decisions about how much to sell.ANS: F DIF: 1 REF: 4-3NAT: Analytic LOC: Supply and demand TOP: Market supply curveMSC: Definitional48. If something happens to alter the quantity supplied at any given price, then we move along the fixed supply curve to a new quantity supplied.ANS: F DIF: 2 REF: 4-3NAT: Analytic LOC: Supply and demand TOP: Supply curveMSC: Interpretive49. A movement along a supply curve is called a change in supply while a shift of the supply curve is called a change in quantity supplied.ANS: F DIF: 2 REF: 4-3NAT: Analytic LOC: Supply and demand TOP: Supply | Quantity supplied MSC: Interpretive50. A decrease in supply shifts the supply curve to the left.ANS: T DIF: 1 REF: 4-3NAT: Analytic LOC: Supply and demand TOP: Supply curveMSC: Definitional51. A reduction in an input price will cause a change in quantity supplied, but not a change in supply.ANS: F DIF: 2 REF: 4-3NAT: Analytic LOC: Supply and demand TOP: Input pricesMSC: Interpretive52. An increase in the price of ink will shift the supply curve for pens to the left.ANS: T DIF: 2 REF: 4-3NAT: Analytic LOC: Supply and demand TOP: Input pricesMSC: Applicative53. If there is an improvement in the technology used to produce a good, then the supply curve for that good will shift to the left.ANS: F DIF: 2 REF: 4-3NAT: Analytic LOC: Supply and demand TOP: TechnologyMSC: Interpretive54. Advances in production technology typically reduce firms’ costs.ANS: T DIF: 2 REF: 4-3NAT: Analytic LOC: Supply and demand TOP: TechnologyMSC: Interpretive55. If a company making frozen orange juice expects the price of its product to be higher next month, it will supply more to the market this month.ANS: F DIF: 2 REF: 4-3NAT: Analytic LOC: Supply and demand TOP: ExpectationsMSC: Applicative56. When a seller expects the price of its product to decrease in the future, the seller's supply curve shifts left now. ANS: F DIF: 2 REF: 4-3NAT: Analytic LOC: Supply and demand TOP: ExpectationsMSC: Interpretive57. An increase in the price of a product and an increase in the number of sellers in the market affect the supplycurve in the same general way.ANS: F DIF: 2 REF: 4-3NAT: Analytic LOC: Supply and demand TOP: Supply curveMSC: Interpretive58. Whenever a determinant of supply other than price changes, the supply curve shifts.ANS: T DIF: 2 REF: 4-3NAT: Analytic LOC: Supply and demand TOP: Supply curveMSC: Interpretive59. A decrease in the price of pizza will shift the supply curve for pizza to the left.ANS: F DIF: 2 REF: 4-3NAT: Analytic LOC: Supply and demand TOP: Supply curveMSC: Applicative60. Supply and demand together determine the price and quantity of a good sold in a market.ANS: T DIF: 1 REF: 4-4NAT: Analytic LOC: Supply and demand TOP: EquilibriumMSC: Definitional61. A market’s equilibrium is the point at which the supply and demand curves intersect.ANS: T DIF: 1 REF: 4-4NAT: Analytic LOC: Supply and demand TOP: EquilibriumMSC: Definitional62. At the equilibrium price, quantity demanded is equal to quantity supplied.ANS: T DIF: 1 REF: 4-4NAT: Analytic LOC: Equilibrium TOP: Equilibrium MSC: Definitional63. The equilibrium price is the same as the market-clearing price.ANS: T DIF: 1 REF: 4-4NAT: Analytic LOC: Equilibrium TOP: Equilibrium MSC: Definitional64. At the equilibrium price, buyers have bought all they want to buy, but sellers have not sold all they want tosell.ANS: F DIF: 1 REF: 4-4NAT: Analytic LOC: Equilibrium TOP: Equilibrium MSC: Definitional65. The actions of buyers and sellers naturally move markets toward equilibrium.ANS: T DIF: 1 REF: 4-4NAT: Analytic LOC: Equilibrium TOP: Equilibrium MSC: Definitional66. When the market price is above the equilibrium price, the quantity of the good demanded exceeds the quantity supplied.ANS: F DIF: 1 REF: 4-4NAT: Analytic LOC: Equilibrium TOP: Equilibrium MSC: Definitional67. When the market price is above the equilibrium price, suppliers are unable to sell all they want to sell. ANS: T DIF: 1 REF: 4-4NAT: Analytic LOC: Equilibrium TOP: Equilibrium MSC: Definitional68. A surplus is the same as an excess demand.ANS: F DIF: 1 REF: 4-4NAT: Analytic LOC: Supply and demand TOP: SurplusMSC: Definitionalword⽂档可⾃由复制编辑208 Chapter 4 /The Market Forces of Supply and Demand69. Sellers respond to a surplus by cutting their prices.ANS: T DIF: 1 REF: 4-4NAT: Analytic LOC: Supply and demand TOP: SurplusMSC: Definitional70. Price will rise to eliminate a surplus.ANS: F DIF: 2 REF: 4-4NAT: Analytic LOC: Equilibrium TOP: Surplus MSC: Interpretive71. When quantity supplied exceeds quantity demanded at the current market price, the market has a surplus and market price will likely rise in the future to eliminate the surplus.ANS: F DIF: 2 REF: 4-4NAT: Analytic LOC: Equilibrium TOP: Surplus MSC: Interpretive72. When the market price is below the equilibrium price, the quantity of the good demanded exceeds the quantity supplied.ANS: T DIF: 1 REF: 4-4NAT: Analytic LOC: Equilibrium TOP: Equilibrium MSC: Definitional73. When the market price is below the equilibrium price, suppliers are unable to sell all they want to sell. ANS: F DIF: 1 REF: 4-4NAT: Analytic LOC: Equilibrium TOP: Equilibrium MSC: Definitional74. A shortage is the same as an excess demand.ANS: T DIF: 1 REF: 4-4NAT: Analytic LOC: Supply and demand TOP: ShortageMSC: Definitional75. Sellers respond to a shortage by cutting their prices.ANS: F DIF: 1 REF: 4-4NAT: Analytic LOC: Supply and demand TOP: ShortageMSC: Definitional76. Price will rise to eliminate a shortage.ANS: T DIF: 2 REF: 4-4NAT: Analytic LOC: Equilibrium TOP: Shortage MSC: Interpretive77. When quantity demanded exceeds quantity supplied at the current market price, the market has a shortage and market price will likely rise in the future to eliminate the shortage.ANS: T DIF: 2 REF: 4-4NAT: Analytic LOC: Equilibrium TOP: Shortage MSC: Interpretive78. Surpluses drive price up while shortages drive price down.ANS: F DIF: 2 REF: 4-4NAT: Analytic LOC: Equilibrium TOP: Shortage | SurplusMSC: Interpretive79. A shortage will occur at any price below equilibrium price and a surplus will occur at any price aboveequilibrium price.ANS: T DIF: 2 REF: 4-4NAT: Analytic LOC: Equilibrium TOP: Shortage | SurplusMSC: Interpretive80. In a market, the price of any good adjusts until quantity demanded equals quantity supplied.ANS: T DIF: 2 REF: 4-4NAT: Analytic LOC: Equilibrium TOP: Equilibrium MSC: Interpretive81. When a supply curve or a demand curve shifts, the equilibrium price and equilibrium quantity change. ANS: T DIF: 1 REF: 4-4NAT: Analytic LOC: Equilibrium TOP: Equilibrium MSC: Definitional82. Demand refers to the amount buyers wish to buy, whereas the quantity demanded refers to the position of the demand curve.ANS: F DIF: 1 REF: 4-4NAT: Analytic LOC: Supply and demandTOP: Demand | Quantity demanded MSC: Definitional83. Supply refers to the position of the supply curve, whereas the quantity supplied refers to the amount supplierswish to sell.ANS: T DIF: 1 REF: 4-4NAT: Analytic LOC: Supply and demand TOP: Supply | Quantity supplied MSC: Definitional84. It is not possible for demand and supply to shift at the same time.ANS: F DIF: 2 REF: 4-4NAT: Analytic LOC: Supply and demand TOP: Supply | DemandMSC: Interpretive85. A decrease in demand will cause a decrease in price, which will cause a decrease in supply.ANS: F DIF: 2 REF: 4-4NAT: Analytic LOC: Supply and demand TOP: EquilibriumMSC: Interpretive86. An increase in demand will cause an increase in price, which will cause an increase in quantity supplied. ANS: T DIF: 2 REF: 4-4NAT: Analytic LOC: Supply and demand TOP: EquilibriumMSC: Interpretive87. An increase in supply will cause a decrease in price, which will cause an increase in demand.ANS: F DIF: 2 REF: 4-4NAT: Analytic LOC: Supply and demand TOP: EquilibriumMSC: Interpretive88. A decrease in supply will cause an increase in price, which will cause a decrease in quantity demanded. ANS: T DIF: 2 REF: 4-4NAT: Analytic LOC: Supply and demand TOP: EquilibriumMSC: Interpretive89. In a market economy, prices are the signals that guide the allocation of scarce resources.ANS: T DIF: 1 REF: 4-5NAT: Analytic LOC: Markets, market failure, and externalitiesTOP: Market economies MSC: Definitionalword⽂档可⾃由复制编辑。

曼昆_微观经济学_原理_第五版_课后习题答案

第三章6．下表描述了Baseballia国两个城市的生产可能性：一个工人每小时生产的红补袜子量一个工人每小时生产的白袜子量A．没有贸易，波士顿一双白袜子价格（用红袜子表示）是多少？芝加哥11双白袜子价格是多少?答：没有贸易时，波士顿1 双白袜子价格是1 双红袜子，芝加哥1 双白袜子价格是2 双红袜子。

B．在每种颜色的袜子生产上，哪个城市有绝对优势？哪个城市有比较优势??答：波士顿在生产红、白袜子上都有绝对优势。

波士顿在生产白袜子上有比较优势，芝加哥在生产红袜子上有比较优势。

C．如果这两个城市相互交易，两个城市将分别出口哪种颜色的袜子?答：如果它们相互交易，波士顿将出口白袜子，而芝加哥出口红袜子。

D．可以进行交易的价格范围是多少?答：白袜子的最高价格是2 双红袜子，最低价格是1 双红袜子。

红袜子的最高价格是1 双白袜子，最低价格是1／2 双白袜子。

7．假定一个美国工人每年能生产100件衬衣或20台电脑，而一个中国工人每年能生产100件衬衣或10台电脑。

A．画出这两个国家的生产可能性边界。

假定没有贸易，每个国家的工人各用一半的时间生产两种物品，在你的图上标出这一点。

答：两个国家的生产可能性边界如图3 一4 所示。

如果没有贸易，一个美国工人把一半的时间用于生产每种物品，则能生产50 件衬衣、10 台电脑；同样，一个中国工人则能生产50 件衬衣、5 台电脑。

图3 一4 生产可能性边界B．如果这两个国家进行贸易，哪个国家将出口衬衣？举出一个具体的数字例子，并在你的图上标出。

哪一个国家将从贸易中获益？解释原因。

答：中国将出口衬衣。

对美国而言，生产一台电脑的机会成本是5 件衬衣，而生产一件衬衣的机会成本为1/5 台电脑。

对中国而言，生产一台电脑的机会成本是10 件衬衣，而生产一件衬衣的机会成本为1/10 台电脑。

因此，美国在生产电脑上有比较优势，中国在生产衬衣上有比较优势，所以中国将出口衬衣。

衬衣的价格在1/5 到1/10 台电脑之间。

曼昆经济学原理英文版文案加习题答案5章ELASTICITY AND ITS APPLICATION

5ELASTICITY AND ITS APPLICATION WHAT’S NEW IN THE S EVENTH EDITION:There are no major changes to this chapter.LEARNING OBJECTIVES:By the end of this chapter, students should understand:the meaning of the elasticity of demand.what determines the elasticity of demand.the meaning of the elasticity of supply.what determines the elasticity of supply.the concept of elasticity in three very different markets (the market for wheat, the market for oil, and the market for illegal drugs).CONTEXT AND PURPOSE:Chapter 5 is the second chapter of a three-chapter sequence that deals with supply and demand and how markets work. Chapter 4 introduced supply and demand. Chapter 5 shows how much buyersand sellers respond to changes in market conditions. Chapter 6 will address the impact of government polices on competitive markets.The purpose of Chapter 5 is to add precision to the supply-and-demand model. We introduce the concept of elasticity, which measures the responsiveness of buyers and sellers to changes in economic variables such as prices and income. The concept of elasticity allows us to make quantitative observations about the impact of changes in supply and demand on equilibrium prices and quantities.KEY POINTS:The price elasticity of demand measures how much the quantity demanded responds to changes in the price. Demand tends to be more elastic if close substitutes are available, if the good is a luxury rather than a necessity, if the market is narrowly defined, or if buyers have substantial time to react to a price change.The price elasticity of demand is calculated as the percentage change in quantity demanded divided by the percentage change in price. If quantity demanded moves proportionately less than the price, then the elasticity is less than one, and demand is said to be inelastic.If quantity demanded moves proportionately more than the price, then the elasticity is greater than one, and demand is said to be elastic.Total revenue, the total amount paid for a good, equals the price of the good times the quantity sold. For inelastic demand curves, total revenue moves in the same direction as the price. For elastic demand curves, total revenue moves in the opposite direction as the price.The income elasticity of demand measures how much the quantity demanded responds tochanges in consumers’ income. The cross-price elasticity of demand measures how much the quantity demanded of one good responds to the price of another good.The price elasticity of supply measures how much the quantity supplied responds to changes in the price. This elasticity often depends on the time horizon under consideration. In most markets, supply is more elastic in the long run than in the short run.The price elasticity of supply is calculated as the percentage change in quantity supplied divided by the percentage change in price. If quantity supplied moves proportionately less than the price, then the elasticity is less than one, and supply is said to be inelastic.If quantity supplied moves proportionately more than the price, then the elasticity is greater than one, and supply is said to be elastic.The tools of supply and demand can be applied in many different kinds of markets. This chapter uses them to analyze the market for wheat, the market for oil, and the market for illegal drugs.CHAPTER OUTLINE:I. The Elasticity of DemandA. Definition of elasticity: a measure of the responsiveness of quantity demanded orquantity supplied to one of its determinants.B. The Price Elasticity of Demand and Its Determinants1. Definition of price elasticity of demand: a measure of how much the quantitydemanded of a good responds to a change in the price of that good, computed as thepercentage change in quantity demanded divided by the percentage change in price.2. Determinants of the Price Elasticity of Demanda. Availability of Close Substitutes: the more substitutes a good has, the moreelastic its demand.b. Necessities versus Luxuries: necessities are more price inelastic.c. Definition of the market: narrowly defined markets (ice cream) have moreelastic demand than broadly defined markets (food).d. Time Horizon: goods tend to have more elastic demand over longer time horizons.C. Computing the Price Elasticity of Demand1. Formula2. Example: the price of ice cream rises by 10% and quantity demanded falls by 20%.Price elasticity of demand = (20%)/(10%) = 23. Because there is an inverse relationship between price and quantity demanded (theprice of ice cream rose by 10% and the quantity demanded fell by 20%), the price elasticity of demand is sometimes reported as a negative number. We will ignorethe minus sign and concentrate on the absolute value of the elasticity.D. The Midpoint Method: A Better Way to Calculate Percentage Changes and Elasticities1. Because we use percentage changes in calculating the price elasticity of demand,the elasticity calculated by going from one point to another on a demand curvewill be different from an elasticity calculated by going from the second point tothe first. This difference arises because the percentage changes are calculatedusing a different base.a. A way around this problem is to use the midpoint method.b. Using the midpoint method involves calculating the percentage change in eitherprice or quantity demanded by dividing the change in the variable by themidpoint between the initial and final levels rather than by the initial levelitself.c. Example: the price rises from $4 to $6 and quantity demanded falls from 120 to80.% change in price = (6 −4)/5 × 100 = 40%% change in quantity demanded = (120 − 80)/100 x 100 = 40%price elasticity of demand = 40/40 = 1E. The Variety of Demand Curves1. Classification of Elasticitya. When the price elasticity of demand is greater than one, demand is defined tobe elastic.b. When the price elasticity of demand is less than one, the demand is defined tobe inelastic.c. When the price elasticity of demand is equal to one, the demand is said to haveunit elasticity.2. In general, the flatter the demand curve that passes through a given point, themore elastic the demand.3. Extreme Casesa. When the price elasticity of demand is equal to zero, the demand is perfectlyinelastic and is a vertical line.b. When the price elasticity of demand is infinite, the demand is perfectlyelastic and is a horizontal line.4. FYI: A Few Elasticities from the Real WorldF. Total Revenue and the Price Elasticity of Demand1. Definition of total revenue: the amount paid by buyers and received by sellers ofa good, computed as the price of the good times the quantity sold.2. If demand is inelastic, the percentage change in price will be greater than thepercentage change in quantity demanded.a. If price rises, quantity demanded falls, and total revenue will rise (becausethe increase in price will be larger than the decrease in quantity demanded).b. If price falls, quantity demanded rises, and total revenue will fall (becausethe fall in price will be larger than the increase in quantity demanded).3. If demand is elastic, the percentage change in quantity demanded will be greaterthan the percentage change in price.a. If price rises, quantity demanded falls, and total revenue will fall (becausethe increase in price will be smaller than the decrease in quantity demanded).b. If price falls, quantity demanded rises, and total revenue will rise (becausethe fall in price will be smaller than the increase in quantity demanded).4. If demand is unit elastic, the percentage change in price will be equal to thepercentage change in quantity demanded.a. If price rises, quantity demanded falls, and total revenue will remain the same(because the increase in price will be equal to the decrease in quantitydemanded).b. If price falls, quantity demanded rises, and total revenue will remain the same(because the fall in price will be equal to the increase in quantity demanded).G. Elasticity and Total Revenue along a Linear Demand Curve1. The slope of a linear demand curve is constant, but the elasticity is not.a. At points with a low price and a high quantity demanded, demand is inelastic.b. At points with a high price and a low quantity demanded, demand is elastic.2. Total revenue also varies at each point along the demand curve.H. Other Demand Elasticities1. Definition of income elasticity of demand: a measure of how much the quantitydemanded of a good responds to a change in consumers’ income, computed as the percentage change in quantity demanded divided by the percentage change in income.a. FormulaFigure 4Note that when demand is elastic and price falls, total revenue rises. Also point out that once demand is inelastic, any further decrease in price% change in quantity demandedIncome elasticity of demand =% change in incomeb. Normal goods have positive income elasticities, while inferior goods havenegative income elasticities.ALTERNATIVE CLASSROOM EXAMPLE:John’s income rises from $20,000 to $22,000 and the quantity of hamburger he buyseach week falls from 2 pounds to 1 pound.% change in quantity demanded = (1−2)/ x 100 = %% change in income = (22,000 −20,000)/21,000 x 100 = %c. Necessities tend to have small income elasticities, while luxuries tend to havelarge income elasticities.2. Definition of cross-price elasticity of demand: a measure of how much the quantitydemanded of one good responds to a change in the price of another good, computedas the percentage change in the quantity demanded of the first good divided by the percentage change in the price of the second good.a. Formulab. Substitutes have positive cross-price elasticities, while complements havenegative cross-price elasticities.ALTERNATIVE CLASSROOM EXAMPLE:The price of apples rises from $ per pound to $ per pound. As a result, thequantity of oranges demanded rises from 8,000 per week to 9,500.% change in quantity of oranges demanded = (9,500 − 8,000)/8,750 x 100 = %% change in price of apples = − / x 100 = 40%II. The Elasticity of SupplyA. The Price Elasticity of Supply and Its Determinants1. Definition of price elasticity of supply: a measure of how much the quantitysupplied of a good responds to a change in the price of that good, computed as thepercentage change in quantity supplied divided by the percentage change in price.2. Determinants of the Price Elasticity of Supplya. Flexibility of sellers: goods that are somewhat fixed in supply (beachfrontproperty) have inelastic supplies.b. Time horizon: supply is usually more inelastic in the short run than in thelong run.B. Computing the Price Elasticity of Supply1. Formula2. Example: the price of milk increases from $ per gallon to $ per gallon and thequantity supplied rises from 9,000 to 11,000 gallons per month.% change in price = –/ × 100 = 10%% change in quantity supplied = (11,000 –9,000)/10,000 × 100 = 20%Price elasticity of supply = (20%)/(10%) = 2C. The Variety of Supply Curves1. In general, the flatter the supply curve that passes through a given point, themore elastic the supply.2. Extreme Casesa. When the elasticity is equal to zero, the supply is said to be perfectlyinelastic and is a vertical line.b. When the elasticity is infinite, the supply is said to be perfectly elastic andis a horizontal line.3. Because firms often have a maximum capacity for production, the elasticity ofsupply may be very high at low levels of quantity supplied and very low at highlevels of quantity supplied.III. Three Applications of Supply, Demand, and ElasticityA. Can Good News for Farming Be Bad News for Farmers1. A new hybrid of wheat is developed that is more productive than those used in thepast. What happens2. Supply increases, price falls, and quantity demanded rises.3. If demand is inelastic, the fall in price is greater than the increase in quantitydemanded and total revenue falls.4. If demand is elastic, the fall in price is smaller than the rise in quantitydemanded and total revenue rises.5. In practice, the demand for basic foodstuffs (like wheat) is usually inelastic.a. This means less revenue for farmers.b. Because farmers are price takers, they still have the incentive to adopt thenew hybrid so that they can produce and sell more wheat.c. This may help explain why the number of farms has declined so dramatically overthe past two centuries.d. This may also explain why some government policies encourage farmers todecrease the amount of crops planted.B. Why Did OPEC Fail to Keep the Price of Oil HighFigure 8Short Run Long Run1. In the 1970s and 1980s, OPEC reduced the amount of oil it was willing to supply toworld markets. The decrease in supply led to an increase in the price of oil and a decrease in quantity demanded. The increase in price was much larger in the short run than the long run. Why2. The demand and supply of oil are much more inelastic in the short run than thelong run. The demand is more elastic in the long run because consumers can adjust to the higher price of oil by carpooling or buying a vehicle that gets bettermileage. The supply is more elastic in the long run because non-OPEC producerswill respond to the higher price of oil by producing more.C. Does Drug Interdiction Increase or Decrease Drug-Related Crime1. The federal government increases the number of federal agents devoted to the waron drugs. What happensa. The supply of drugs decreases, which raises the price and leads to a reductionin quantity demanded. If demand is inelastic, total expenditure on drugs (equalto total revenue) will increase. If demand is elastic, total expenditure willfall.b. Thus, because the demand for drugs is likely to be inelastic, drug-relatedcrime may rise.2. What happens if the government instead pursued a policy of drug educationa. The demand for drugs decreases, which lowers price and quantity supplied. Totalexpenditure must fall (because both price and quantity fall).b. Thus, drug education should not increase drug-related crime.SOLUTIONS TO TEXT PROBLEMS:Quick Quizzes1. The price elasticity of demand is a measure of how much the quantity demanded of agood responds to a change in the price of that good, computed as the percentage change in quantity demanded divided by the percentage change in price.When demand is inelastic (a price elasticity less than 1), a price increase raisestotal revenue, and a price decrease reduces total revenue. When demand is elastic (a price elasticity greater than 1), a price increase reduces total revenue, and a price decrease increases total revenue. When demand is unit elastic (a price elasticity equal to 1), a change in price does not affect total revenue.2. The price elasticity of supply is a measure of how much the quantity supplied of agood responds to a change in the price of that good, computed as the percentage change in quantity supplied divided by the percentage change in price.The price elasticity of supply might be different in the long run than in theshort run because over short periods of time, firms cannot easily change the sizes Figure 9(a) Drug Interdiction (b) Drug Educationof their factories to make more or less of a good. Thus, in the short run, thequantity supplied is not very responsive to the price. However, over longerperiods, firms can build new factories, expand existing factories, close oldfactories, or they can enter or exit a market. So, in the long run, the quantitysupplied can respond substantially to a change in price.3. A drought that destroys half of all farm crops could be good for farmers (at leastthose unaffected by the drought) if the demand for the crops is inelastic. Theshift to the left of the supply curve leads to a price increase that will raisetotal revenue if the price elasticity of demand is less than 1.No one farmer would have an incentive to destroy her crops in the absence of adrought because she takes the market price as given. Only if all farmersdestroyed a portion of their crops together, for example through a governmentprogram, would this plan work to make farmers better off.Questions for Review1. The price elasticity of demand measures how much quantity demanded responds to achange in price. The income elasticity of demand measures how much quantitydemanded responds to changes in consumers' income.2. The determinants of the price elasticity of demand include the availability ofclose substitutes, whether the good is a necessity or a luxury, the breadth of thedefinition of the market, and the time horizon. Goods with close substitutes havegreater elasticities, luxury goods have greater price elasticities thannecessities, goods in more narrowly defined markets have greater elasticities, andthe elasticity of demand is greater the longer the time horizon.3. An elasticity greater than one means that demand is elastic. When the elasticityis greater than one, the percentage change in quantity demanded exceeds thepercentage change in price. When the elasticity equals zero, demand is perfectly inelastic. There is no change in quantity demanded when there is a change in price.4. Figure 1 presents a supply-and-demand diagram, showing the equilibrium price, P,the equilibrium quantity, Q, and the total revenue received by producers. Total revenue equals the equilibrium price times the equilibrium quantity, which is the area of the rectangle shown in the figure.Figure 15. If demand is elastic, an increase in price reduces total revenue. With elasticdemand, the quantity demanded falls by a greater percentage than the price rises.As a result, total revenue moves in the opposite direction as the price. Thus, if price rises, total revenue falls.6. A good with income elasticity less than zero is called an inferior good because asincome rises, the quantity demanded declines.7. The price elasticity of supply is calculated as the percentage change in quantitysupplied divided by the percentage change in price. It measures how much quantity supplied responds to changes in price.8. If a fixed quantity of a good is available and no more can be made, the priceelasticity of supply is zero. Regardless of the percentage change in price, therewill be no change in the quantity supplied.9. Destruction of half of the fava bean crop is more likely to hurt fava bean farmersif the demand for fava beans is very elastic. Destruction of half of the cropcauses the supply curve to shift to the left resulting in a higher price of favabeans. When demand is very elastic, an increase in price leads to a decrease intotal revenue because the decrease in quantity demanded outweighs the increase inprice.Quick Check Multiple Choice1. a2. b3. d4. c5. a6. cProblems and Applications1. a. Mystery novels have more elastic demand than required textbooks because mysterynovels have close substitutes and are a luxury good, while required textbooksare a necessity with no close substitutes. If the price of mystery novels wereto rise, readers could substitute other types of novels, or buy fewer novelsaltogether. But if the price of required textbooks were to rise, students wouldhave little choice but to pay the higher price. Thus, the quantity demanded ofrequired textbooks is less responsive to price than the quantity demanded ofmystery novels.b. Beethoven recordings have more elastic demand than classical music recordingsin general. Beethoven recordings are a narrower market than classical musicrecordings, so it is easier to find close substitutes for them. If the price of Beethoven recordings were to rise, people could substitute other classicalrecordings, like Mozart. But if the price of all classical recordings were torise, substitution would be more difficult. (A transition from classical musicto rap is unlikely!) Thus, the quantity demanded of classical recordings isless responsive to price than the quantity demanded of Beethoven recordings.c. Subway rides during the next five years have more elastic demand than subwayrides during the next six months. Goods have a more elastic demand over longertime horizons. If the fare for a subway ride was to rise temporarily, consumers could not switch to other forms of transportation without great expense orgreat inconvenience. But if the fare for a subway ride was to remain high for a long time, people would gradually switch to alternative forms of transportation.As a result, the quantity demanded of subway rides during the next six monthswill be less responsive to changes in the price than the quantity demanded ofsubway rides during the next five years.d. Root beer has more elastic demand than water. Root beer is a luxury with closesubstitutes, while water is a necessity with no close substitutes. If the price of water were to rise, consumers have little choice but to pay the higher price.But if the price of root beer were to rise, consumers could easily switch toother sodas or beverages. So the quantity demanded of root beer is moreresponsive to changes in price than the quantity demanded of water.2. a. For business travelers, the price elasticity of demand when the price oftickets rises from $200 to $250 is [(2,000 – 1,900)/1,950]/[(250 – 200)/225]= = . For vacationers, the price elasticity of demand when the price oftickets rises from $200 to $250 is [(800 – 600)/700] / [(250 – 200)/225] == .b. The price elasticity of demand for vacationers is higher than the elasticityfor business travelers because vacationers can choose a substitute more easilythan business travelers. For example, vacationers can choose a different mode of transportation (like driving or taking the train), a different destination, a different departure date, and a different return date. They may also choose to not travel at all. Business travelers are less likely to do so because their schedules are less adaptable.3. a. The percentage change in price is equal to – / x 100 = 20%. If the priceelasticity of demand is , quantity demanded will fall by 4% in the short run [ ]. If the price elasticity of demand is , quantity demanded will fall by 14% in the long run [].b. Over time, consumers can make adjustments to their homes by purchasingalternative heat sources such as natural gas or electric furnaces. Thus, they can respond more easily to the change in the price of heating oil in the long run than in the short run.4. If quantity demanded fell, price must have increased according to the law ofdemand. For a price increase to increase total revenue, the percentage increase in the price must be greater than the percentage decline in quantity demanded. Therefore, demand is inelastic.5. , a. The effect on the market for coffee beans is shown in Figure 2. When ahurricane destroys half of the crop, the supply of coffee beans decreases, the price of coffee beans increases, and the quantity decreases.QuantityPrice Figure 2Demand S 1 S 2b. The effect on the market for cups of coffee is shown in Figure 2. When theprice of coffee beans, an important input into the production of a cup ofcoffee, increases, the supply of cups of coffee decreases, the price of a cup of coffee increases, and the quantity decreases.Because cups of coffee have an inelastic demand, when the price of a cup ofcoffee increases, the total expenditure on coffee increases.c. The effect on the market for donuts is shown in Figure 3. When the price ofcoffee increases and the quantity demanded of coffee decreases, consumersdemand fewer donuts because coffee and donuts are complements. When demanddecreases, the price of donuts decreases.Because donuts have an inelastic demand, when the price of donuts decreases,the total expenditure on donuts decreases.6. a. If your income is $10,000, your price elasticity of demand as the price of DVDsrises from $8 to $10 is [(40 – 32)/36]/[(10 – 8)/9] = = 1. If your income is $12,000, the elasticity is [(50 – 45)/]/[(10 – 8)/9] = = .b. If the price is $12, your income elasticity of demand as your income increasesfrom $10,000 to $12,000 is [(30 – 24)/27]/[(12,000 – 10,000)/11,000] = = . Price Figure 3If the price is $16, your income elasticity of demand as your income increases from $10,000 to $12,000 is [(12 – 8)/10]/[(12,000 – 10,000)/11,000] = = .7. a. If Maria always spends one-third of her income on clothing, then her incomeelasticity of clothing demand is one, because maintaining her clothingexpenditures as a constant fraction of her income means the percentage changein her quantity of clothing must equal her percentage change in income.b. Maria's price elasticity of clothing demand is also one, because everypercentage point increase in the price of clothing would lead her to reduce her quantity purchased by the same percentage.c. Because Maria spends a smaller proportion of her income on clothing, then forany given price, her quantity demanded will be lower. Thus, her demand curvehas shifted to the left. Because she will again spend a constant fraction ofher income on clothing, her income and price elasticities of demand remain one.8. a. The percentage change in price (using the midpoint formula) is – / × 100%= %. Therefore, the price elasticity of demand is = , which is very elastic.b. Because the demand is inelastic, the Transit Authority's revenue rises when thefare rises.c. The elasticity estimate might be unreliable because it is only the first monthafter the fare increase. As time goes by, people may switch to other means oftransportation in response to the price increase. So the elasticity may belarger in the long run than it is in the short run.9. Walt's price elasticity of demand is zero, because he wants the same quantityregardless of the price. Jessie's price elasticity of demand is one, because he spends the same amount on gas, no matter what the price, which means hispercentage change in quantity is equal to the percentage change in price.10. a. With a price elasticity of demand of , reducing the quantity demanded ofcigarettes by 20% requires a 50% increase in price, because 20/50 = . With the price of cigarettes currently $2, this would require an increase in the priceto $ a pack using the midpoint method (note that ($ – $2)/$ = .50).b. The policy will have a larger effect five years from now than it does one yearfrom now. The elasticity is larger in the long run, because it may take sometime for people to reduce their cigarette usage. The habit of smoking is hardto break in the short run.c. Because teenagers do not have as much income as adults, they are likely to havea higher price elasticity of demand. Also, adults are more likely to beaddicted to cigarettes, making it more difficult to reduce their quantitydemanded in response to a higher price.11. To determine whether you should increase or decrease the price of admissions, youneed to know if the demand is elastic or inelastic. If demand is elastic, adecline in the price of admissions will increase total revenue. If demand isinelastic, an increase in the price of admissions will cause total revenue to rise.12. A worldwide drought could increase the total revenue of farmers if the priceelasticity of demand for grain is inelastic. The drought reduces the supply of grain, but if demand is inelastic, the reduction of supply causes a large increase in price. Total farm revenue would rise as a result. If there is only a drought in Kansas, Kansas’ production is not a large enough proportion of the total farm product to have much impact on the price. As a result, price does not change (or changes by only a slight amount), while the output by Kansas farmers declines, thus reducing their income.。

曼昆经济学原理答案英文版

曼昆经济学原理答案英文版一、选择题1、在经济学中，什么是GDP？A.国内生产总值B.国民生产总值C.国内总收入D.国民总收入答案：A.国内生产总值（Gross Domestic Product，GDP）是指一个国家在一定时期内所有常住单位的生产活动的最终成果。

2、GDP的计算方法是什么？A.收入法B.支出法C.生产法D.混合法答案：B.支出法。

GDP可以通过对一国所有常住单位的商品和服务的最终消费支出、资本形成总额和货物与服务净出口进行计算，这种计算方法被称为支出法。

3、在经济学中，什么是通货膨胀？A.货币贬值B.物价上涨C.货币供应增加D.以上都不是答案：A.通货膨胀是指商品和服务的总体价格水平上升，导致货币购买力下降。

4、什么是货币政策？A.政府调节货币供应量的政策B.政府调节利率的政策C.政府调节汇率的政策D.以上都不是答案：A.货币政策是指中央银行通过控制货币供应量来调节利率和影响经济活动的政策。

二、简答题1、请简述GDP的概念及作用。

答案：GDP是指一个国家在一定时期内所有常住单位的生产活动的最终成果。

GDP是国民经济核算的核心指标，也是衡量一个国家经济状况和发展水平的重要指标。

它反映了整个国家经济运行的有效性，以及国民收入分配的公平性。

2、请简述通货膨胀的原因及影响。

答案：通货膨胀的原因有多种，包括货币供应量增加、需求拉动、成本推动等。

其中，货币供应量增加是最主要的原因。

当货币供应量增加时，物价上涨，导致货币购买力下降。

通货膨胀会对经济产生负面影响，包括降低消费者购买力、增加企业成本、扭曲价格信号等。

通货膨胀还会导致社会不稳定和政治风险。

曼昆的经济学原理课件是经济学教育中的重要资源，它以深入浅出的方式解释了经济学的基本原理和概念。

本文将对这些原理进行概述，并解释它们在现实生活中的应用。

曼昆的经济学原理主要包括微观经济学和宏观经济学两个部分。

微观经济学主要研究个体经济单位的行为和决策，如消费者、企业和政府。

曼昆哈佛大学经济学原理第四章

An increase in income...
0.50
D1
0 1 2 3 4 5 6 7 8 9 10 11 12
Movement along the demand curve. Caused by a change in the price of
the product.
Harcourt, Inc. items and derived items copyright © 2001 by Harcourt, Inc.
Market Type: A Competitive Market
A competitive market is a market. . .
with many buyers and sellers. that is not controlled by any one person. in which a narrow range of prices are established that buyers and sellers act upon.
A
0
12
Harcourt, Inc. items and derived items copyright © 2001 by Harcourt, Inc.
20
D1
Number of Cigarettes Smoked per Day
Change in Quantity Demanded versus Change in Demand
Price of Cigarettes per Pack
$4.00
Changes in Quantity Demanded
A tax that raises the
C
price of cigarettes results in a movement

曼昆经济学原理英文版文案加习题答案5章elasticityanditsapplication

5ELASTICITY AND ITS APPLICATION WHAT’S NEW IN THE S EVENTH EDITION:There are no major changes to this chapter.LEARNING OBJECTIVES:By the end of this chapter, students should understand:the meaning of the elasticity of demand.what determines the elasticity of demand.the meaning of the elasticity of supply.what determines the elasticity of supply.the concept of elasticity in three very different markets (the market for wheat, the market for oil, and the market for illegal drugs).CONTEXT AND PURPOSE:Chapter 5 is the second chapter of a three-chapter sequence that deals with supply and demand and how markets work. Chapter 4 introduced supply and demand. Chapter 5 shows how much buyers and sellers respond to changes in market conditions. Chapter 6 will address the impact of government polices on competitive markets.The purpose of Chapter 5 is to add precision to the supply-and-demand model. We introduce the concept of elasticity, which measures the responsiveness of buyers and sellers to changes in economic variables such as prices and income. The concept of elasticity allows us to make quantitative observations about the impact of changes in supply and demand on equilibrium prices and quantities.KEY POINTS:The price elasticity of demand measures how much the quantity demanded responds to changes in the price. Demand tends to be more elastic if close substitutes are available, if the good is a luxury rather than a necessity, if the market is narrowly defined, or if buyers have substantial time to react to a price change.The price elasticity of demand is calculated as the percentage change in quantity demanded divided by the percentage change in price. If quantity demanded moves proportionately less than the price, then the elasticity is less than one, and demand is said to be inelastic.If quantity demanded moves proportionately more than the price, then the elasticity is greater than one, and demand is said to be elastic.Total revenue, the total amount paid for a good, equals the price of the good times the quantity sold. For inelastic demand curves, total revenue moves in the same direction as the price. For elastic demand curves, total revenue moves in the opposite direction as the price.The income elasticity of demand measures how much the quantity demanded responds tochanges in consumers’ income. The cross-price elasticity of demand measures how much the quantity demanded of one good responds to the price of another good.The price elasticity of supply measures how much the quantity supplied responds to changes in the price. This elasticity often depends on the time horizon under consideration. In most markets, supply is more elastic in the long run than in the short run.The price elasticity of supply is calculated as the percentage change in quantity supplied divided by the percentage change in price. If quantity supplied moves proportionately less than the price, then the elasticity is less than one, and supply is said to be inelastic.If quantity supplied moves proportionately more than the price, then the elasticity is greater than one, and supply is said to be elastic.The tools of supply and demand can be applied in many different kinds of markets. This chapter uses them to analyze the market for wheat, the market for oil, and the market for illegal drugs.CHAPTER OUTLINE:I. The Elasticity of DemandA. Definition of elasticity: a measure of the responsiveness of quantity demanded orquantity supplied to one of its determinants.B. The Price Elasticity of Demand and Its Determinants1. Definition of price elasticity of demand: a measure of how much the quantitydemanded of a good responds to a change in the price of that good, computed as thepercentage change in quantity demanded divided by the percentage change in price.2. Determinants of the Price Elasticity of Demanda. Availability of Close Substitutes: the more substitutes a good has, the moreelastic its demand.b. Necessities versus Luxuries: necessities are more price inelastic.c. Definition of the market: narrowly defined markets (ice cream) have moreelastic demand than broadly defined markets (food).d. Time Horizon: goods tend to have more elastic demand over longer time horizons.C. Computing the Price Elasticity of Demand1. Formula2. Example: the price of ice cream rises by 10% and quantity demanded falls by 20%.Price elasticity of demand = (20%)/(10%) = 23. Because there is an inverse relationship between price and quantity demanded (theprice of ice cream rose by 10% and the quantity demanded fell by 20%), the price elasticity of demand is sometimes reported as a negative number. We will ignorethe minus sign and concentrate on the absolute value of the elasticity.D. The Midpoint Method: A Better Way to Calculate Percentage Changes and Elasticities1. Because we use percentage changes in calculating the price elasticity of demand,the elasticity calculated by going from one point to another on a demand curvewill be different from an elasticity calculated by going from the second point to the first. This difference arises because the percentage changes are calculatedusing a different base.a. A way around this problem is to use the midpoint method.b. Using the midpoint method involves calculating the percentage change in eitherprice or quantity demanded by dividing the change in the variable by themidpoint between the initial and final levels rather than by the initial levelitself.c. Example: the price rises from $4 to $6 and quantity demanded falls from 120 to80.% change in price = (6 −4)/5 × 100 = 40%% change in quantity demanded = (120 − 80)/100 x 100 = 40%price elasticity of demand = 40/40 = 1E. The Variety of Demand Curves1. Classification of Elasticitya. When the price elasticity of demand is greater than one, demand is defined tobe elastic.b. When the price elasticity of demand is less than one, the demand is defined tobe inelastic.c. When the price elasticity of demand is equal to one, the demand is said to haveunit elasticity.2. In general, the flatter the demand curve that passes through a given point, themore elastic the demand.3. Extreme Casesa. When the price elasticity of demand is equal to zero, the demand is perfectlyinelastic and is a vertical line.b. When the price elasticity of demand is infinite, the demand is perfectlyelastic and is a horizontal line.4. FYI: A Few Elasticities from the Real WorldF. Total Revenue and the Price Elasticity of Demand1. Definition of total revenue: the amount paid by buyers and received by sellers ofa good, computed as the price of the good times the quantity sold.2. If demand is inelastic, the percentage change in price will be greater than thepercentage change in quantity demanded.a. If price rises, quantity demanded falls, and total revenue will rise (becausethe increase in price will be larger than the decrease in quantity demanded).b. If price falls, quantity demanded rises, and total revenue will fall (becausethe fall in price will be larger than the increase in quantity demanded).3. If demand is elastic, the percentage change in quantity demanded will be greaterthan the percentage change in price.a. If price rises, quantity demanded falls, and total revenue will fall (becausethe increase in price will be smaller than the decrease in quantity demanded).b. If price falls, quantity demanded rises, and total revenue will rise (becausethe fall in price will be smaller than the increase in quantity demanded).4. If demand is unit elastic, the percentage change in price will be equal to thepercentage change in quantity demanded.a. If price rises, quantity demanded falls, and total revenue will remain the same(because the increase in price will be equal to the decrease in quantitydemanded).b. If price falls, quantity demanded rises, and total revenue will remain the same(because the fall in price will be equal to the increase in quantity demanded).G. Elasticity and Total Revenue along a Linear Demand Curve1. The slope of a linear demand curve is constant, but the elasticity is not.a. At points with a low price and a high quantity demanded, demand is inelastic.b. At points with a high price and a low quantity demanded, demand is elastic.2. Total revenue also varies at each point along the demand curve.H. Other Demand Elasticities1. Definition of income elasticity of demand: a measure of how much the quantitydemanded of a good responds to a change in consumers’ income, computed as the percentage change in quantity demanded divided by the percentage change in income.a. Formulab. Normal goods have positive income elasticities, while inferior goods havenegative income elasticities.Figure 4Note that when demand is elastic and price falls, total revenue rises. Also point out that once demand is inelastic, any further decrease in price results in a decrease in total revenue.% change in quantity demandedIncome elasticity of demand =% change in incomeALTERNATIVE CLASSROOM EXAMPLE:John’s income rises from $20,000 to $22,000 and the quantity of hamburger he buyseach week falls from 2 pounds to 1 pound.% change in quantity demanded = (1−2)/ x 100 = %% change in income = (22,000 −20,000)/21,000 x 100 = %income elasticity = %/% =Point out that hamburger is an inferior good for John.c. Necessities tend to have small income elasticities, while luxuries tend to havelarge income elasticities.2. Definition of cross-price elasticity of demand: a measure of how much the quantitydemanded of one good responds to a change in the price of another good, computedas the percentage change in the quantity demanded of the first good divided by the percentage change in the price of the second good.a. Formulab. Substitutes have positive cross-price elasticities, while complements havenegative cross-price elasticities.ALTERNATIVE CLASSROOM EXAMPLE:The price of apples rises from $ per pound to $ per pound. As a result, thequantity of oranges demanded rises from 8,000 per week to 9,500.% change in quantity of oranges demanded = (9,500 − 8,000)/8,750 x 100 = %% change in price of apples = − / x 100 = 40%cross-price elasticity = %/40% =Because the cross-price elasticity is positive, the two goods are substitutes.II. The Elasticity of SupplyA. The Price Elasticity of Supply and Its Determinants1. Definition of price elasticity of supply: a measure of how much the quantitysupplied of a good responds to a change in the price of that good, computed as thepercentage change in quantity supplied divided by the percentage change in price.2. Determinants of the Price Elasticity of Supplya. Flexibility of sellers: goods that are somewhat fixed in supply (beachfrontproperty) have inelastic supplies.b. Time horizon: supply is usually more inelastic in the short run than in thelong run.B. Computing the Price Elasticity of Supply1. Formula2. Example: the price of milk increases from $ per gallon to $ per gallon and thequantity supplied rises from 9,000 to 11,000 gallons per month.% change in price = –/ × 100 = 10%% change in quantity supplied = (11,000 –9,000)/10,000 × 100 = 20%Price elasticity of supply = (20%)/(10%) = 2C. The Variety of Supply Curves1. In general, the flatter the supply curve that passes through a given point, themore elastic the supply.2. Extreme Casesa. When the elasticity is equal to zero, the supply is said to be perfectlyinelastic and is a vertical line.b. When the elasticity is infinite, the supply is said to be perfectly elastic andis a horizontal line.3. Because firms often have a maximum capacity for production, the elasticity ofsupply may be very high at low levels of quantity supplied and very low at highlevels of quantity supplied.III. Three Applications of Supply, Demand, and ElasticityA. Can Good News for Farming Be Bad News for Farmers1. A new hybrid of wheat is developed that is more productive than those used in thepast. What happens2. Supply increases, price falls, and quantity demanded rises.3. If demand is inelastic, the fall in price is greater than the increase in quantitydemanded and total revenue falls.4. If demand is elastic, the fall in price is smaller than the rise in quantitydemanded and total revenue rises.5. In practice, the demand for basic foodstuffs (like wheat) is usually inelastic.a. This means less revenue for farmers.b. Because farmers are price takers, they still have the incentive to adopt thenew hybrid so that they can produce and sell more wheat.c. This may help explain why the number of farms has declined so dramatically overthe past two centuries.d. This may also explain why some government policies encourage farmers todecrease the amount of crops planted.B. Why Did OPEC Fail to Keep the Price of Oil HighFigure 8Short Run Long Run1. In the 1970s and 1980s, OPEC reduced the amount of oil it was willing to supply toworld markets. The decrease in supply led to an increase in the price of oil and a decrease in quantity demanded. The increase in price was much larger in the short run than the long run. Why2. The demand and supply of oil are much more inelastic in the short run than thelong run. The demand is more elastic in the long run because consumers can adjust to the higher price of oil by carpooling or buying a vehicle that gets bettermileage. The supply is more elastic in the long run because non-OPEC producerswill respond to the higher price of oil by producing more.C. Does Drug Interdiction Increase or Decrease Drug-Related Crime1. The federal government increases the number of federal agents devoted to the waron drugs. What happensa. The supply of drugs decreases, which raises the price and leads to a reductionin quantity demanded. If demand is inelastic, total expenditure on drugs (equalto total revenue) will increase. If demand is elastic, total expenditure willfall.b. Thus, because the demand for drugs is likely to be inelastic, drug-relatedcrime may rise.2. What happens if the government instead pursued a policy of drug educationa. The demand for drugs decreases, which lowers price and quantity supplied. Totalexpenditure must fall (because both price and quantity fall).b. Thus, drug education should not increase drug-related crime.SOLUTIONS TO TEXT PROBLEMS:Quick Quizzes1. The price elasticity of demand is a measure of how much the quantity demanded of agood responds to a change in the price of that good, computed as the percentage change in quantity demanded divided by the percentage change in price.When demand is inelastic (a price elasticity less than 1), a price increase raisestotal revenue, and a price decrease reduces total revenue. When demand is elastic (a price elasticity greater than 1), a price increase reduces total revenue, and a price decrease increases total revenue. When demand is unit elastic (a price elasticity equal to 1), a change in price does not affect total revenue.2. The price elasticity of supply is a measure of how much the quantity supplied of agood responds to a change in the price of that good, computed as the percentage change in quantity supplied divided by the percentage change in price.The price elasticity of supply might be different in the long run than in theshort run because over short periods of time, firms cannot easily change the sizes of their factories to make more or less of a good. Thus, in the short run, the quantity supplied is not very responsive to the price. However, over longer periods, firms can build new factories, expand existing factories, close old factories, or they can enter or exit a market. So, in the long run, the quantity supplied can respond substantially to a change in price.3. A drought that destroys half of all farm crops could be good for farmers (at leastthose unaffected by the drought) if the demand for the crops is inelastic. The shift to the left of the supply curve leads to a price increase that will raise total revenue if the price elasticity of demand is less than 1.Figure 9(a) Drug Interdiction (b) Drug EducationNo one farmer would have an incentive to destroy her crops in the absence of adrought because she takes the market price as given. Only if all farmersdestroyed a portion of their crops together, for example through a governmentprogram, would this plan work to make farmers better off.Questions for Review1. The price elasticity of demand measures how much quantity demanded responds to achange in price. The income elasticity of demand measures how much quantitydemanded responds to changes in consumers' income.2. The determinants of the price elasticity of demand include the availability ofclose substitutes, whether the good is a necessity or a luxury, the breadth of thedefinition of the market, and the time horizon. Goods with close substitutes havegreater elasticities, luxury goods have greater price elasticities thannecessities, goods in more narrowly defined markets have greater elasticities, andthe elasticity of demand is greater the longer the time horizon.3. An elasticity greater than one means that demand is elastic. When the elasticityis greater than one, the percentage change in quantity demanded exceeds thepercentage change in price. When the elasticity equals zero, demand is perfectlyinelastic. There is no change in quantity demanded when there is a change in price.4. Figure 1 presents a supply-and-demand diagram, showing the equilibrium price, P,the equilibrium quantity, Q, and the total revenue received by producers. Totalrevenue equals the equilibrium price times the equilibrium quantity, which is thearea of the rectangle shown in the figure.Figure 15. If demand is elastic, an increase in price reduces total revenue. With elasticdemand, the quantity demanded falls by a greater percentage than the price rises.As a result, total revenue moves in the opposite direction as the price. Thus, ifprice rises, total revenue falls.6. A good with income elasticity less than zero is called an inferior good because asincome rises, the quantity demanded declines.7. The price elasticity of supply is calculated as the percentage change in quantitysupplied divided by the percentage change in price. It measures how much quantitysupplied responds to changes in price.8. If a fixed quantity of a good is available and no more can be made, the priceelasticity of supply is zero. Regardless of the percentage change in price, therewill be no change in the quantity supplied.9. Destruction of half of the fava bean crop is more likely to hurt fava bean farmersif the demand for fava beans is very elastic. Destruction of half of the cropcauses the supply curve to shift to the left resulting in a higher price of favabeans. When demand is very elastic, an increase in price leads to a decrease intotal revenue because the decrease in quantity demanded outweighs the increase inprice.Quick Check Multiple Choice1. a2. b3. d4. c5. a6. cProblems and Applications1. a. Mystery novels have more elastic demand than required textbooks because mysterynovels have close substitutes and are a luxury good, while required textbooksare a necessity with no close substitutes. If the price of mystery novels wereto rise, readers could substitute other types of novels, or buy fewer novelsaltogether. But if the price of required textbooks were to rise, students wouldhave little choice but to pay the higher price. Thus, the quantity demanded ofrequired textbooks is less responsive to price than the quantity demanded ofmystery novels.b. Beethoven recordings have more elastic demand than classical music recordingsin general. Beethoven recordings are a narrower market than classical musicrecordings, so it is easier to find close substitutes for them. If the price ofBeethoven recordings were to rise, people could substitute other classicalrecordings, like Mozart. But if the price of all classical recordings were torise, substitution would be more difficult. (A transition from classical musicto rap is unlikely!) Thus, the quantity demanded of classical recordings isless responsive to price than the quantity demanded of Beethoven recordings.c. Subway rides during the next five years have more elastic demand than subwayrides during the next six months. Goods have a more elastic demand over longertime horizons. If the fare for a subway ride was to rise temporarily, consumerscould not switch to other forms of transportation without great expense orgreat inconvenience. But if the fare for a subway ride was to remain high for a long time, people would gradually switch to alternative forms of transportation. As a result, the quantity demanded of subway rides during the next six months will be less responsive to changes in the price than the quantity demanded of subway rides during the next five years.d. Root beer has more elastic demand than water. Root beer is a luxury with closesubstitutes, while water is a necessity with no close substitutes. If the price of water were to rise, consumers have little choice but to pay the higher price. But if the price of root beer were to rise, consumers could easily switch toother sodas or beverages. So the quantity demanded of root beer is moreresponsive to changes in price than the quantity demanded of water.2. a. For business travelers, the price elasticity of demand when the price oftickets rises from $200 to $250 is [(2,000 – 1,900)/1,950]/[(250 – 200)/225] = = . For vacationers, the price elasticity of demand when the price oftickets rises from $200 to $250 is [(800 – 600)/700] / [(250 – 200)/225] = = .b. The price elasticity of demand for vacationers is higher than the elasticityfor business travelers because vacationers can choose a substitute more easily than business travelers. For example, vacationers can choose a different mode of transportation (like driving or taking the train), a different destination, a different departure date, and a different return date. They may also choose to not travel at all. Business travelers are less likely to do so because their schedules are less adaptable.3. a. The percentage change in price is equal to – / x 100 = 20%. If the priceelasticity of demand is , quantity demanded will fall by 4% in the short run [ ]. If the price elasticity of demand is , quantity demanded will fall by 14% in the long run [ ].b. Over time, consumers can make adjustments to their homes by purchasingalternative heat sources such as natural gas or electric furnaces. Thus, they can respond more easily to the change in the price of heating oil in the long run than in the short run.4. If quantity demanded fell, price must have increased according to the law ofdemand. For a price increase to increase total revenue, the percentage increase in the price must be greater than the percentage decline in quantity demanded. Therefore, demand is inelastic.5. , a. The effect on the market for coffee beans is shown in Figure 2. When ahurricane destroys half of the crop, the supply of coffee beans decreases, the price of coffee beans increases, and the quantity decreases.Price DemandS 1 S 2b. The effect on the market for cups of coffee is shown in Figure 2. When theprice of coffee beans, an important input into the production of a cup ofcoffee, increases, the supply of cups of coffee decreases, the price of a cup of coffee increases, and the quantity decreases.Because cups of coffee have an inelastic demand, when the price of a cup ofcoffee increases, the total expenditure on coffee increases.c. The effect on the market for donuts is shown in Figure 3. When the price ofcoffee increases and the quantity demanded of coffee decreases, consumersdemand fewer donuts because coffee and donuts are complements. When demanddecreases, the price of donuts decreases.Because donuts have an inelastic demand, when the price of donuts decreases,the total expenditure on donuts decreases.6. a. If your income is $10,000, your price elasticity of demand as the price of DVDsrises from $8 to $10 is [(40 – 32)/36]/[(10 – 8)/9] = = 1. If your income is $12,000, the elasticity is [(50 – 45)/]/[(10 – 8)/9] = = .b. If the price is $12, your income elasticity of demand as your income increasesfrom $10,000 to $12,000 is [(30 – 24)/27]/[(12,000 – 10,000)/11,000] = = . If the price is $16, your income elasticity of demand as your income increases from $10,000 to $12,000 is [(12 – 8)/10]/[(12,000 – 10,000)/11,000] = = .7. a. If Maria always spends one-third of her income on clothing, then her incomeelasticity of clothing demand is one, because maintaining her clothingPriceFigure 3expenditures as a constant fraction of her income means the percentage changein her quantity of clothing must equal her percentage change in income.b. Maria's price elasticity of clothing demand is also one, because everypercentage point increase in the price of clothing would lead her to reduce her quantity purchased by the same percentage.c. Because Maria spends a smaller proportion of her income on clothing, then forany given price, her quantity demanded will be lower. Thus, her demand curvehas shifted to the left. Because she will again spend a constant fraction ofher income on clothing, her income and price elasticities of demand remain one.8. a. The percentage change in price (using the midpoint formula) is – / × 100%= %. Therefore, the price elasticity of demand is = , which is very elastic.b. Because the demand is inelastic, the Transit Authority's revenue rises when thefare rises.c. The elasticity estimate might be unreliable because it is only the first monthafter the fare increase. As time goes by, people may switch to other means oftransportation in response to the price increase. So the elasticity may belarger in the long run than it is in the short run.9. Walt's price elasticity of demand is zero, because he wants the same quantityregardless of the price. Jessie's price elasticity of demand is one, because he spends the same amount on gas, no matter what the price, which means hispercentage change in quantity is equal to the percentage change in price.10. a. With a price elasticity of demand of , reducing the quantity demanded ofcigarettes by 20% requires a 50% increase in price, because 20/50 = . With the price of cigarettes currently $2, this would require an increase in the priceto $ a pack using the midpoint method (note that ($ – $2)/$ = .50).b. The policy will have a larger effect five years from now than it does one yearfrom now. The elasticity is larger in the long run, because it may take sometime for people to reduce their cigarette usage. The habit of smoking is hardto break in the short run.c. Because teenagers do not have as much income as adults, they are likely to havea higher price elasticity of demand. Also, adults are more likely to beaddicted to cigarettes, making it more difficult to reduce their quantitydemanded in response to a higher price.11. To determine whether you should increase or decrease the price of admissions, youneed to know if the demand is elastic or inelastic. If demand is elastic, adecline in the price of admissions will increase total revenue. If demand isinelastic, an increase in the price of admissions will cause total revenue to rise.。

曼昆经济学原理第五版答案答案3

SOLUTIONS TO TEXT PROBLEMS:Quick Quizzes1. Figure 1 shows a production possibilities frontier for Robinson Crusoe between gathering coconutsand catching fish. If Crusoe lives by himself, this frontier limits his consumption of coconuts and fish, but if he can trade with natives on the island he will be able to consume at a point outside his production possibilities frontier.Figure 12. Crusoe’s opportunity cost of catching one fish is 10 coconuts, since he can gather 10 coconuts inthe same amou nt of time it takes to catch one fish. Friday’s opportunity cost of catching one fish is 15 coconuts, since he can gather 30 coconuts in the same amount of time it takes to catch two fish. Friday has an absolute advantage in catching fish, since he can catch two per hour, while Crusoe can only catch one per hour. But Crusoe has a comparative advantage in catching fish, since his opportunity cost of catching a fish is less than Friday’s.3. If the world’s fastest typist happens to be trained in brain sur gery, he should hire a secretary. Hehas an absolute advantage in typing, but a comparative advantage in brain surgery, since hisopportunity cost in brain surgery is low compared to the opportunity cost for other people.Questions for Review1. Absolute advantage reflects a comparison of the productivity of one person, firm, or nation to thatof another, while comparative advantage is based on the relative opportunity costs of the persons, firms, or nations. While a person, firm, or nation may have an absolute advantage in producing every good, they can't have a comparative advantage in every good.2. Many examples are possible. Suppose, for example, that Roger can prepare a fine meal of hotdogs and macaroni in just ten minutes, while it takes Anita twenty minutes. And Roger can do all the wash in three hours, while it takes Anita four hours. Roger has an absolute advantage in both cooking and doing the wash, but Anita has a comparative advantage in doing the wash (the wash takes the same amount of time as 12 meals, while it takes Roger 18 meals' worth of time).353. Comparative advantage is more important for trade than absolute advantage. In the example inproblem 2, Anita and Roger will complete their chores more quickly if Anita does at least some of the wash and Roger cooks the fine meals for both, because Anita has a comparative advantage in doing the wash, while Roger has a comparative advantage in cooking.4. A nation will export goods for which it has a comparative advantage because it has a smalleropportunity cost of producing those goods. As a result, citizens of all nations are able to consume quantities of goods that are outside their production possibilities frontiers.5. Economists oppose policies that restrict trade among nations because trade allows all countries toachieve greater prosperity by allowing them to receive the gains from comparative advantage.Restrictions on trade hurt all countries.Problems and Applicat ions1. In the text example of the farmer and the rancher, the farmer's opportunity cost of producing oneounce of meat is 4 ounces of potatoes because for every 8 hours of work, he can produce 8 ounces of meat or 32 ounces of potatoes. With limited time at his disposal, producing an ounce of meat means he gives up the opportunity to produce 4 ounces of potatoes. Similarly, the rancher'sopportunity cost of producing one ounce of meat is 2 ounces of potatoes because for every 8 hours of work, she can produce 24 ounces of meat or 48 ounces of potatoes. With limited time at her disposal, producing an ounce of meat means she gives up the opportunity to produce 2 ounces of potatoes.2. a. See Figure 2. If Maria spends all five hours studying economics, she can read 100 pages,so that is the vertical intercept of the production possibilities frontier. If she spends allfive hours studying sociology, she can read 250 pages, so that is the horizontal intercept.The time costs are constant, so the production possibilities frontier is a straight line.Figure 2b. It takes Maria two hours to read 100 pages of sociology. In that time, she could read 40pages of economics. So the opportunity cost of 100 pages of sociology is 40 pages ofeconomics.3. a.b. See Figure 3. With 100 million workers and four cars per worker, if either economy weredevoted completely to cars, it could make 400 million cars. Since a U.S. worker canproduce 10 tons of grain, if the United States produced only grain it would produce 1,000million tons. Since a Japanese worker can produce 5 tons of grain, if Japan produced onlygrain it would produce 500 million tons. These are the intercepts of the productionpossibilities frontiers shown in the figure. Note that since the tradeoff between cars andgrain is constant, the production possibilities frontier is a straight line.Figure 3c. Since a U.S. worker produces either 4 cars or 10 tons of grain, the opportunity cost of 1 caris 2½ tons of grain, which is 10 divided by 4. Since a Japanese worker produces either 4cars or 5 tons of grain, the opportunity cost of 1 car is1 1/4 tons of grain, which is 5 divided by 4. Similarly, the U.S. opportunity cost of 1 ton ofgrain is 2/5 car (4 divided by 10) and the Japanese opportunity cost of 1 ton of grain is 4/5car (4 divided by 5). This gives the following table:d. Neither country has an absolute advantage in producing cars, since they're equallyproductive (the same output per worker); the United States has an absolute advantage inproducing grain, since it is more productive (greater output per worker).e. Japan has a comparative advantage in producing cars, since it has a lower opportunity costin terms of grain given up. The United States has a comparative advantage in producinggrain, since it has a lower opportunity cost in terms of cars given up.f. With half the workers in each country producing each of the goods, the United Stateswould produce 200 million cars (that is 50 million workers times 4 cars each) and 500million tons of grain (50 million workers times 10 tons each). Japan would produce 200million cars (50 million workers times 4 cars each) and 250 million tons of grain (50 millionworkers times 5 tons each).g. From any situation with no trade, in which each country is producing some cars and somegrain, suppose the United States changed 1 worker from producing cars to producing grain.That worker would produce 4 fewer cars and 10 additional tons of grain. Then supposethe United States offers to trade 7 tons of grain to Japan for 4 cars. The United States willdo this because it values 4 cars at 10 tons of grain, so it will be better off if the trade goesthrough. Suppose Japan changes 1 worker from producing grain to producing cars.That worker would produce 4 more cars and 5 fewer tons of grain. Japan will take thetrade because it values 4 cars at 5 tons of grain, so it will be better off. With the trade andthe change of 1 worker in both the United States and Japan, each country gets the sameamount of cars as before and both get additional tons of grain (3 for the United States and2 for Japan). Thus by trading and changing their production, both countries are betteroff.4. a. Pat's opportunity cost of making a pizza is 1/2 gallon of root beer, since she could brew 1/2gallon in the time (2 hours) it takes her to make a pizza. Pat has an absolute advantage inmaking pizza since she can make one in two hours, while it takes Kris four hours. Kris'opportunity cost of making a pizza is 2/3 gallons of root beer, since she could brew 2/3 ofa gallon in the time (4 hours) it takes her to make a pizza. Since Pat's opportunity cost ofmaking pizza is less than Kris's, Pat has a comparative advantage in making pizza.b. Since Pat has a comparative advantage in making pizza, she will make pizza and exchangeit for root beer that Kris makes.c. The highest price of pizza in terms of root beer that will make both roommates better off is2/3 of a gallon of root beer. If the price were higher than that, then Kris would prefermaking her own pizza (at an opportunity cost of 2/3 of a gallon of root beer) rather thantrading for pizza that Pat makes. The lowest price of pizza in terms of root beer that willmake both roommates better off is 1/2 gallon of root beer. If the price were lower thanthat, then Pat would prefer making her own root beer (she can make 1/2 gallon of rootbeer instead of making a pizza) rather than trading for root beer that Kris makes.5. a. Since a Canadian worker can make either two cars a year or 30 bushels of wheat, theopportunity cost of a car is 15 bushels of wheat. Similarly, the opportunity cost of abushel of wheat is 1/15 of a car. The opportunity costs are the reciprocals of each other.b. See Figure 4. If all 10 million workers produce two cars each, they produce a total of 20million cars, which is the vertical intercept of the production possibilities frontier. If all 10million workers produce 30 bushels of wheat each, they produce a total of 300 millionbushels, which is the horizontal intercept of the production possibilities frontier. S ince thetradeoff between cars and wheat is always the same, the production possibilities frontier isa straight line.If Canada chooses to consume 10 million cars, it will need 5 million workers devoted to carproduction. That leaves 5 million workers to produce wheat, who will produce a total of150 million bushels (5 million workers times 30 bushels per worker). This is shown aspoint A on Figure 4.c. If the United States buys 10 million cars from Canada and Canada continues to consume10 million cars, then Canada will need to produce a total of 20 million cars. So Canada willbe producing at the vertical intercept of the production possibilities frontier. But if Canadagets 20 bushels of wheat per car, it will be able to consume 200 million bushels of wheat,along with the 10 million cars. This is shown as point B in the figure. Canada shouldaccept the deal because it gets the same number of cars and 50 million more bushes ofwheat.Figure 46. Though the professor could do both writing and data collection faster than the student (that is, hehas an absolute advantage in both), his time is limited. If the professor's comparative advantage is in writing, it makes sense for him to pay a student to collect the data, since that is the student's comparative advantage.7. a. English workers have an absolute advantage over Scottish workers in producing scones,since English workers produce more scones per hour (50 vs. 40). Scottish workers havean absolute advantage over English workers in producing sweaters, since Scottish workersproduce more sweaters per hour (2 vs. 1). Comparative advantage runs the same way.English workers, who have an opportunity cost of 1/50 sweater per scone (1 sweater perhour divided by 50 scones per hour), have a comparative advantage in scone productionover Scottish workers, who have an opportunity cost of 1/20 sweater per scone (2sweaters per hour divided by 40 scones per hour). Scottish workers, who have anopportunity cost of 20 scones per sweater (40 scones per hour divided by 2 sweaters perhour), have a comparative advantage in sweater production over English workers, whohave an opportunity cost of 50 scones per sweater (50 scones per hour divided by 1sweater per hour).Chapter 3/Interdependence and the Gains from Trade 40b. If England and Scotland decide to trade, Scotland will produce sweaters and trade them forscones produced in England. A trade with a price between 20 and 50 scones per sweaterwill benefit both countries, as they'll be getting the traded good at a lower price than theiropportunity cost of producing the good in their own country.c. Even if a Scottish worker produced just one sweater per hour, the countries would still gainfrom trade, because Scotland would still have a comparative advantage in producingsweaters. Its opportunity cost for sweaters would be higher than before (40 scones persweater, instead of 20 scones per sweater before). But there are still gains from tradesince England has a higher opportunity cost (50 scones per sweater).8. a. With no trade, one pair of white socks trades for one pair of red socks in Boston, sinceproductivity is the same for the two types of socks. The price in Chicago is 2 pairs of redsocks per pair of white socks.b. Boston has an absolute advantage in the production of both types of socks, since a workerin Boston produces more (3 pairs of socks per hour) than a worker in Chicago (2 pairs ofred socks per hour or 1 pair of white socks per hour).Chicago has a comparative advantage in producing red socks, since the opportunity cost ofproducing a pair of red socks in Chicago is 1/2 pair of white socks, while the opportunitycost of producing a pair of red socks in Boston is 1 pair of white socks. Boston has acomparative advantage in producing white socks, since the opportunity cost of producing apair of white socks in Boston is 1 pair of red socks, while the opportunity cost of producinga pair of white socks in Chicago is 2 pairs of red socks.c. If they trade socks, Boston will produce white socks for export, since it has the compara tiveadvantage in white socks, while Chicago produces red socks for export, which is Chicago'scomparative advantage.d. Trade can occur at any price between 1 and 2 pairs of red socks per pair of white socks.At a price lower than 1 pair of red socks per pair of white socks, Boston will choose toproduce its own red socks (at a cost of 1 pair of red socks per pair of white socks) insteadof buying them from Chicago. At a price higher than 2 pairs of red socks per pair of whitesocks, Chicago will choose to produce its own white socks (at a cost of 2 pairs of red socksper pair of white socks) instead of buying them from Boston.9. a. The cost of all goods is lower in Germany than in France in the sense that all goods can beproduced with fewer worker hours.b. The cost of any good for which France has a comparative advantage is lower in Francethan in Germany. Though Germany produces all goods with less labor, that labor may bemore valuable in the production of some goods and services. So the cost of production, interms of opportunity cost, will be lower in France for some goods.c. Trade between Germany and France will benefit both countries. For each good in which ithas a comparative advantage, each country should produce more goods than it consumes,trading the rest to the other country. Total consumption will be higher in both countriesas a result.10. a. True; two countries can achieve gains from trade even if one of the countries has anabsolute advantage in the production of all goods. All that's necessary is that eachChapter 3/Interdependence and the Gains from Trade 41 country have a comparative advantage in some good.b. False; it is not true that some people have a comparative advantage in everything they do.In fact, no one can have a comparative advantage in everything. Comparative advantage reflects the opportunity cost of one good or activity in terms of another. If you have acomparative advantage in one thing, you must have a comparative disadvantage in theother thing.c. False; it is not true that if a trade is good for one person, it can't be good for the other one.Trades can and do benefit both sides especially trades based on comparative advantage.If both sides didn't benefit, trades would never occur.。

经济学原理曼昆英文

经济学原理曼昆英文1. Economics as a Social Science: In this chapter, the author introduces the study of economics as a social science that explores how individuals, firms, and societies make decisions about resource allocation.2. The Role of Incentives: This chapter explores how individuals respond to incentives and how they influence decision-making in economics. Various types of incentives, such as financial rewards and punishments, are discussed.3. Supply and Demand: The concept of supply and demand is explained in this chapter. It delves into how the interaction between buyers and sellers in a market determines the equilibrium price and quantity of a product.4. Elasticity and Its Applications: Elasticity, a measure of responsiveness, is discussed in this chapter. The various types of elasticity, including price elasticity of demand and income elasticity of demand, are explained and their applications are explored.5. Consumer Choice: This chapter explores how individuals make choices as consumers, considering factors such as preferences, constraints, and budget constraints. Utility theory and indifference curves are introduced as tools to understand consumer choice.6. Production and Costs: The author discusses how firms make decisions regarding production and cost in this chapter. Topics covered include production functions, costs of production, and theconcept of economies of scale.7. Perfect Competition: This chapter explores the characteristics of perfect competition, including the large number of buyers and sellers, homogenous products, and ease of entry and exit. It also examines the implications of perfect competition on market outcomes.8. Monopoly: The concept of monopoly, where a single firm controls the market, is discussed in this chapter. The author analyzes the sources of monopoly power and its implications for prices and output in the market.9. Market Failures and Government Intervention: This chapter examines market failures, situations where the market fails to allocate resources efficiently. Different types of market failures, such as externalities and public goods, are explained, along with the role of government intervention in correcting these failures.10. Externalities: Externalities, or the consequences of economic activities on third parties, are explored in this chapter. The author discusses positive and negative externalities and their implications for resource allocation.11. Public Goods and Common Resources: This chapter focuses on the characteristics of public goods and common resources. It discusses the free-rider problem and the challenges in providing public goods efficiently.12. Markets for Factors of Production: The author explores themarkets for factors of production, including labor and capital, in this chapter. Wage determination, discrimination, and other factors influencing the prices of these factors are analyzed.13. The Economics of Income Inequality: Income inequality and its causes are discussed in this chapter. The author explores different theories and factors that contribute to income inequality, as well as its implications for society and policy considerations.14. The Theory of Consumer Choice: This chapter delves deeper into the theory of consumer choice, examining topics such as consumer preferences, budget constraints, and the concept of utility maximization.15. Frontiers of Microeconomics: The final chapter explores the frontiers of microeconomics, including topics such as behavioral economics, game theory, and the economics of information. The author discusses how these fields have expanded our understanding of economic behavior.。

曼昆经济学原理第五版课后答案第三篇供给与需求

第三篇供给与需求(Ⅱ)：市场和福利第七章消费者、生产者与市场效率复习题1．解释买者的支付意愿、消费者剩余和需求曲线如何相关。

答：需求曲线反映了买者的支付意愿。

在任何一种数量时，需求曲线给出的价格表示边际买者的支付意愿。

需求曲线以下和价格以上的总面积是一种物品或劳务市场上所有买者消费者剩余的总和。

2．解释卖者的成本、生产者剩余和供给曲线如何相关。

答：供给曲线的高度与卖者的成本相关。

在任何一种数量时，供给曲线给出的价格表示边际卖者的成本。

价格之下和供给曲线以上的面积衡量市场的生产者剩余。

3．在供求图中，说明市场均衡时的生产者和消费者剩余。

答：APE的面积代表消费者剩余；PBE的面积代表生产者剩余。

图7－1 供求图4．什么是效率?它是经济决策者的惟一目标吗?答：效率是指资源配置使社会所有成员得到的总剩余最大化的性质。

除了效率外，经济决策者还应该关心平等。

实际上，市场交易的好处很像在市场参与者之间分割一块蛋糕，经济决策者不仅要关心如何将经济蛋糕做大，即效率；还要考虑如何在市场参与者之间分这块蛋糕，这就涉及公平问题。

5．看不见的手有什么作用?答：每一个市场参与者都会尽力追求自己的利益，看不见的手指引他们在相互竞争中达到一个并非他们本意想要达到的目的，这就是市场均衡点。

在均衡点上，消费者剩余和生产者剩余总和最大化，整个社会福利达到最大。

6．说出两种市场失灵的名字。

解释为什么每一种都可能使市场结果无效率。

答：市场失灵包括市场势力和外部性。

如果某一市场上存在市场势力，即只有极少部分(可能是一个)买者或卖者可以控制市场价格，他们就会使价格趋向于对他们这一小部分人有益的水平。

于是，市场价格和数量背离供求平衡，社会福利达不到最大，市场失去效率。

外部性是某些市场参与者的行为对旁观者福利的影响。

它使市场福利还要取决于买者评价和卖者成本之外的其他因素。

由于买者和卖者在决定消费和生产时并没有考虑这种负作用。

所以，从整个社会角度来看，市场均衡可能是无效率的。

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1. Definition of automatic stabilizers: changes in fiscal policy that stimulate aggregatedemand when the economy goes into a recession without policymakers having totake any deliberate action.2. The most important automatic stabilizer is the tax system.a. When the economy falls into a recession, incomes and profits fall.b. The personal income tax depends on the level of households’ incomes and the corporateincome tax depends on the level of firm profits.c. This implies that the government’s tax revenue falls during a recession. This tax cutstimulates aggregate demand and reduces the magnitude of this economic downturn.3. Government spending is also an automatic stabilizer.a. More individuals become eligible for transfer payments during a recession.b. These transfer payments provide additional income to recipients, stimulating spending.c. Thus, just like the tax system, our system of transfer payments helps to reduce the sizeof short-run economic fluctuations.SOLUTIONS TO TEXT PROBLEMS:Quick Quizzes1. According to the theory of liquidity preference, the interest rate adjusts to balance the supplyand demand for money. Therefore, a decrease in the money supply will increase theequilibrium interest rate. This decrease in the money supply reduces aggregate demandbecause the higher interest rate causes households to buy fewer houses, reducing thedemand for residential investment, and causes firms to spend less on new factories and newequipment, reducing business investment.2. If the government reduces spending on highway construction by $10 billion, the aggregate-demand curve shifts to the left because government purchases are lower. The shift to theleft of the aggregate-demand curve could be more than $10 billion if the multiplier effectoutweighs the crowding-out effect, or it could be less than $10 billion if the crowding-outeffect outweighs the multiplier effect.3. If people become pessimistic about the future, they will spend less, causing the aggregate-demand curve to shift to the left. If the Fed wants to stabilize aggregate demand, it shouldincrease the money supply. The increase in the money supply will cause the interest rate todecline, thus stimulating residential and business investment. The Fed might choose not to dothis because by the time the policy action takes effect, the long lag time might mean theeconomy would have recovered on its own, and the increase in the money supply will causeinflation.1. The theory of liquidity preference is Keynes's theory of how the interest rate is determined.According to the theory, the aggregate-demand curve slopes downward because: (1) ahigher price level raises money demand; (2) higher money demand leads to a higher interest rate; and (3) a higher interest rate reduces the quantity of goods and services demanded.Thus, the price level has a negative relationship with the quantity of goods and servicesdemanded.2. A decrease in the money supply shifts the money-supply curve to the left. The equilibriuminterest rate will rise. The higher interest rate reduces consumption and investment, soaggregate demand falls. Thus, the aggregate-demand curve shifts to the left.3. If the government spends $3 billion to buy police cars, aggregate demand might increase bymore than $3 billion because of the multiplier effect on aggregate demand. Aggregatedemand might increase by less than $3 billion because of the crowding-out effect onaggregate demand.4. If pessimism sweeps the country, households reduce consumption spending and firms reduceinvestment, so aggregate demand falls. If the Fed wants to stabilize aggregate demand, it must increase the money supply, reducing the interest rate, which will induce households to save less and spend more and will encourage firms to invest more, both of which willincrease aggregate demand. If the Fed does not increase the money supply, Congress could increase government purchases or reduce taxes to increase aggregate demand.5. Government policies that act as automatic stabilizers include the tax system and governmentspending through the unemployment-benefit system. The tax system acts as an automatic stabilizer because when incomes are high, people pay more in taxes, so they cannot spend as much. When incomes are low, so are taxes; thus, people can spend more. The result is that spending is partly stabilized. Government spending through the unemployment-benefit system acts as an automatic stabilizer because in recessions the government transfers money to the unemployed so their incomes do not fall as much and thus their spending will not fall as much.1. a. When more ATMs are available, money demand is reduced and the money-demand curveshifts to the left from MD1 to MD2, as shown in Figure 6. If the Fed does not change the money supply, which is at MS1, the interest rate will decline from r1 to r2. The decline inthe interest rate shifts the aggregate-demand curve to the right, as consumption andinvestment increase.b. If the Fed wants to stabilize aggregate demand, it should reduce the money supply to MS, so the interest rate will remain at r1 and aggregate demand will not change.22. a. When the Fed’s bond traders buy bonds in open-market operations, the money-supplycurve shifts to the right from MS1 to MS2, as shown in Figure 1. The result is a decline in the interest rate.Figure 1Figure 2b. When an increase in credit card availability reduces the cash people hold, the money-demand curve shifts to the left from MD1 to MD2, as shown in Figure 2. The result is a decline in the interest rate.c. When the Federal Reserve reduces reserve requirements, the money supply increases, sothe money-supply curve shifts to the right from MS1 to MS2, as shown in Figure 1. The result is a decline in the interest rate.d. When households decide to hold more money to use for holiday shopping, the money-demand curve shifts to the right from MD1 to MD2, as shown in Figure 3. The result is a rise in the interest rate.Figure 3e. When a wave of optimism boosts business investment and expands aggregate demand,money demand increases from MD1 to MD2 in Figure 3. The increase in money demand increases the interest rate.Figure 43. a. The increase in the money supply will cause the equilibrium interest rate to decline, asshown in Figure 4. Households will increase spending and will invest in more new housing. Firms too will increase investment spending. This will cause the aggregate demand curve to shift to the right as shown in Figure 5.Price LevelQuantity of Output P 1AD 1AD 2P 2Y 1Y 2Short-run Aggregate SupplyFigure 5b. As shown in Figure 5, the increase in aggregate demand will cause an increase in bothoutput and the price level in the short run.c. When the economy makes the transition from its short-run equilibrium to its long-runequilibrium, short-run aggregate supply will decline, causing the price level to rise even further. d. The increase in the price level will cause an increase in the demand for money, raisingthe equilibrium interest rate.e. Yes. While output initially rises because of the increase in aggregate demand, it will fallonce short-run aggregate supply declines. Thus, there is no long-run effect of the increase in the money supply on real output.Figure 64. A tax cut that is permanent will have a bigger impact on consumer spending and aggregatedemand. If the tax cut is permanent, consumers will view it as adding substantially to their financial resources, and they will increase their spending substantially. If the tax cut istemporary, consumers will view it as adding just a little to their financial resources, so they will not increase spending as much. 5. a. The current situation is shown in Figure 7.Price LevelQuantity of OutputShort-run Aggregate Suppl yAggregate DemandLong-run Aggregate Suppl yFigure 7b. The Fed will want to stimulate aggregate demand. Thus, it will need to lower the interestrate by increasing the money supply. This could be achieved if the Fed purchases government bonds from the public.Figure 8c. As shown in Figure 8, the Fed's purchase of government bonds shifts the supply ofmoney to the right, lowering the interest rate.d. The Fed's purchase of government bonds will increase aggregate demand as consumersand firms respond to lower interest rates. Output and the price level will rise as shown in Figure 9.Figure 96. a. Legislation allowing banks to pay interest on checking deposits increases the return tomoney relative to other financial assets, thus increasing money demand.b. If the money supply remained constant (at MS1), the increase in the demand for moneywould have raised the interest rate, as shown in Figure 10. The rise in the interest ratewould have reduced consumption and investment, thus reducing aggregate demand and output.c. To maintain a constant interest rate, the Fed would need to increase the money supplyfrom MS1 to MS2. Then aggregate demand and output would be unaffected.Figure 107. a. If there is no crowding out, then the multiplier equals 1/(1 – MPC). Because themultiplier is 3, then MPC = 2/3.b. If there is crowding out, then the MPC would be larger than 2/3. An MPC that is largerthan 2/3 would lead to a larger multiplier than 3, which is then reduced down to 3 by the crowding-out effect.8. a. The initial effect of the tax reduction of $20 billion is to increase aggregate demand by$20 billion x 3/4 (the MPC) = $15 billion.b. Additional effects follow this initial effect as the added incomes are spent. The secondround leads to increased consumption spending of $15 billion x 3/4 = $11.25 billion. The third round gives an increase in consumption of $11.25 billion x 3/4 = $8.44 billion. The effects continue indefinitely. Adding them all up gives a total effect that depends on the multiplier. With an MPC of 3/4, the multiplier is 1/(1 – 3/4) = 4. So the total effect is $15 billion x 4 = $60 billion.c. Government purchases have an initial effect of the full $20 billion, because they increaseaggregate demand directly by that amount. The total effect of an increase in government purchases is thus $20 billion x 4 = $80 billion. So government purchases lead to a bigger effect on output than a tax cut does. The difference arises because governmentpurchases affect aggregate demand by the full amount, but a tax cut is partly saved byconsumers, and therefore does not lead to as much of an increase in aggregate demand.d. The government could increase taxes by the same amount it increases its purchases.9. a. If the marginal propensity to consume is 0.8, the spending multiplier will be 1/(1-0.8) =5. Therefore, the government would have to increase spending by $400/5 = $80 billionto close the recessionary gap.b. With an MPC of 0.8, the tax multiplier is (0.8)(1/(1-0.8)) = (0.8)(5) = 4. Therefore, thegovernment would need to cut taxes by $400 billion/4 = $100 billion to close therecessionary gap.c. If the central bank was to hold the money supply constant, my answer would be largerbecause crowding out would occur.d. They would have to raise both government spending and taxes by $400 billion. Theincrease in government purchases would result in a boost of $2,000 billion, while thehigher taxes would reduce spending by $1,600 billion. This leaves a $400 billion rise inaggregate spending.10. If government spending increases, aggregate demand rises, so money demand rises. Theincrease in money demand leads to a rise in the interest rate and thus a decline in aggregate demand if the Fed does not respond. But if the Fed maintains a fixed interest rate, it will increase money supply, so aggregate demand will not decline. Thus, the effect on aggregate demand from an increase in government spending will be larger if the Fed maintains a fixed interest rate.11. a. Expansionary fiscal policy is more likely to lead to a short-run increase in investment ifthe investment accelerator is large. A large investment accelerator means that theincrease in output caused by expansionary fiscal policy will induce a large increase ininvestment. Without a large accelerator, investment might decline because the increase in aggregate demand will raise the interest rate.b. Expansionary fiscal policy is more likely to lead to a short-run increase in investment ifthe interest sensitivity of investment is small. Because fiscal policy increases aggregatedemand, thus increasing money demand and the interest rate, the greater the sensitivity of investment to the interest rate the greater the decline in investment will be, which will offset the positive accelerator effect.12. a. Tax revenue declines when the economy goes into a recession because taxes are closelyrelated to economic activity. In a recession, people's incomes and wages fall, as do firms' profits, so taxes on these things decline.b. Government spending rises when the economy goes into a recession because morepeople get unemployment-insurance benefits, welfare benefits, and other forms ofincome support.c. If the government were to operate under a strict balanced-budget rule, it would have toraise tax rates or cut government spending in a recession. Both would reduce aggregate demand, making the recession more severe.13. a. If there were a contraction in aggregate demand, the Fed would need to increase themoney supply to increase aggregate demand and stabilize the price level, as shown inFigure 11. By increasing the money supply, the Fed is able to shift the aggregate-demand curve back to AD1 from AD2. This policy stabilizes output and the price level.Figure 11b. If there were an adverse shift in short-run aggregate supply, the Fed would need todecrease the money supply to stabilize the price level, shifting the aggregate-demand curve to the left from AD1 to AD2, as shown in Figure 12. This worsens the recession caused by the shift in aggregate supply. To stabilize output, the Fed would need to increase the money supply, shifting the aggregate-demand curve from AD1 to AD3.However, this action would raise the price level.Figure 12。