曼昆经济学原理第三版答案
《经济学原理·曼昆·第三版》第24章
参考资料：美国CPI篮子中有什么？
案例：北京的CPI的计算流程
严格按照国家统计局《流通和消费价格统计调查方 案》的要求：
1. 2. 3. 4. 5.
选择代表规格品。 抽选价格调查点。 计算居民消费价格指数的权数。 价格调查及计算平均价格。 计算居民消费价格指数。
24.1.2 衡量生活费用中的问题 Problems in Measuring The Cost of Living 消费物价指数的目的是衡量生活费用的变动。换句话说，消 费物价指数要确定为了保持生活水平不变，收入应该增加多 少。但是，消费物价指数并不是生活费用的完美衡量指标， 这个指数有三个广泛承认但又难于解决的问题：
上半年 7.9%0日）国家统计局公布了2009年1月份我国居民消费价格 指数和工业品出厂价格指数。统计显示，2009年1月份我国居民消费价 格总水平同比上涨1.0%，1月份工业品出厂价格同比下降3.3％。
24.1.1 如何计算消费者物价指数 How The Consumer Price Index Is Calculated
2005年美元的薪水＝1931年美元的薪水×2005年物价/1931年物价 ＝80000×195/15.2＝1026316（美元）
案例：指数先生进入好莱坞
24.2.2 指数化 INDEXATION
正如我们刚刚说明的，当比较不同时期的美元数字时，要用 物价指数来校正通货膨胀的影响。在经济中的许多地方都表 现出这种校正。当某一美元量根据法律或合约自动地按通货 膨胀校正时，这种美元量就称为通货膨胀的指数化。
24.1消费者物价指数 THE CONSUMER PRICE INDEX
消费者物价指数是普通消费者购买的物品与劳务总 费用的衡量指标。在这一部分我们讨论如何计算消 费物价指数，以及在这种衡量中出现了什么问题； 我们还要讨论如何比较消费物价指数与GDP平减指 数。
曼昆经济学原理试题及答案
曼昆经济学原理试题及答案一、名词解释(每小题 5 分，共 50 分)机会成本科斯定理搭便车囚徒困境菲利普斯曲线供给侧凯恩斯革命看不见的手比较优势外部性二、简述题(第 11、12、13 题各 12 分， 14 题 14 分，共 50 分)1.简要描述银行存款的创建过程。
2.简述失业的根源及其类型。
3.简要描述节俭的对与错。
4.根据有关经济学原理，简析我国森林减少、珍稀动物来绝的原因及解决的措施。
三、论述题(每小题 25 分，共计 50 分)1.讨论人民币升值对中国经济的影响。
2.论述政府公共投资对国民经济的作用。
一、名词解释(每一个子话题 5 分，共 50 分)1.机会成本:指人们利用一定资源获得某种收入时所抛却的在其他可能的用途中所能够获取的最大收入。
生产一单位的某种商品的机会成本是指生产者所抛却的使用相同的生产要素在其他生产用途中所能得到的最高收入。
机会成本的存在需要三个前提条件。
第一，资源是稀缺的；第二，资源具有多种生产用途；第三，资源的投无限制访问。
在从机会成本的角度审视生产过程时，创造商需要将生产要素投入到效益最大的项目中，以避免生产浪费，实现资源的最优配置。
机会成本的概念是基于资源的稀缺性。
在经济资源稀缺的前提下，当一个社会或者企业利用一定的经济资源生产一定数量的一种或者几种产品时，这些经济资源不能同时用于其他生产用途。
也就是说，这个社会或者这个企业能够获得的一定数量的产品收入，是以抛却利用同样的经济资源生产其他产品所能获得的收入为代价的。
这也是机会成本的原因。
因此，一个社会生产一种产品的实际成本是它不能生产其他产品的成本。
因此，机会成本的含义是，任何生产资源或者生产要素一般都有各种不同的方式或者机会，也就是说，它可以用于生产各种产品。
然而，当一定数量的特定资源用于生产 a 类产品时，它们不能同时用于生产 B 类产品。
因此，生产一种产品的实际成本是不生产 B 产品的成本，或者等于这种资源生产 B 产品可能获得的最大回报。
经济学原理第三版习题答案
SOLUTIONS TO TEXT PROBLEMS:Quick Quizzes1. When a competitive firm doubles the amount it sells, the price remains the same, so its totalrevenue doubles.2. The price faced by a profit-maximizing firm is equal to its marginal cost because if price were abovemarginal cost, the firm could increase profits by increasing output, while if price were belowmarginal cost, the firm could increase profits by decreasing output.A profit-maximizing firm decides to shut down in the short run when price is less than averagevariable cost. In the long run, a firm will exit a market when price is less than average total cost.3. In the long run, with free entry and exit, the price in the market is equal to both a firm’s marginalcost and its average total cost, as Figure 1 shows. The firm chooses its quantity so that marginal cost equals price; doing so ensures that the firm is maximizing its profit. In the long run, entry into and exit from the industry drive the price of the good to the minimum point on theaverage-total-cost curve.Figure 1Questions for Review1. A competitive firm is a firm in a market in which: (1) there are many buyers and many sellers inthe market; (2) the goods offered by the various sellers are largely the same; and (3) usually firms can freely enter or exit the market.2. Figure 2 shows the cost curves for a typical firm. For a given price (such as P*), the level of outputthat maximizes profit is the output where marginal cost equals price (Q*), as long as price is greater than average variable cost at that point (in the short run), or greater than average total cost (in the long run).Figure 23. A firm will shut down temporarily if the revenue it would get from producing is less than thevariable costs of production. This occurs if price is less than average variable cost.4. A firm will exit a market if the revenue it would get if it stayed in business is less than its total cost.This occurs if price is less than average total cost.5. A firm's price equals marginal cost in both the short run and the long run. In both the short runand the long run, price equals marginal revenue. The firm should increase output as long asmarginal revenue exceeds marginal cost, and reduce output if marginal revenue is less thanmarginal cost. Profits are maximized when marginal revenue equals marginal cost.6. The firm's price equals the minimum of average total cost only in the long run. In the short run,price may be greater than average total cost, in which case the firm is making profits, or price may be less than average total cost, in which case the firm is making losses. But the situation isdifferent in the long run. If firms are making profits, other firms will enter the industry, which will lower the price of the good. If firms are making losses, they will exit the industry, which will raise the price of the good. Entry or exit continues until firms are making neither profits nor losses. At that point, price equals average total cost.7. Market supply curves are typically more elastic in the long run than in the short run. In acompetitive market, since entry or exit occurs until price equals the minimum of average total cost, the supply curve is perfectly elastic in the long run.Problems and Applications1. A competitive market is one in which: (1) there are many buyers and many sellers in the market;(2) the goods offered by the various sellers are largely the same; and (3) usually firms can freelyenter or exit the market. Of these goods, bottled water is probably the closest to a competitive market. Tap water is a natural monopoly because there's only one seller. Cola and beer are not perfectly competitive because every brand is slightly different.2. Since a new customer is offering to pay $300 for one dose, marginal revenue between 200 and 201doses is $300. So we must find out if marginal cost is greater than or less than $300. To do this, calculate total cost for 200 doses and 201 doses, and calculate the increase in total cost.Multiplying quantity by average total cost, we find that total cost rises from $40,000 to $40,401, so marginal cost is $401. So your roommate should not make the additional dose.3. a. Remembering that price equals marginal cost when firms are maximizing profit, we knowthe marginal cost must be 30 cents, since that is the price.b. The industry is not in long-run equilibrium since price exceeds average total cost.4. Once you have ordered the dinner, its cost is sunk, so it does not represent an opportunity cost.As a result, the cost of the dinner should not influence your decision about stuffing yourself.5. Since Bob’s average total cost is $280/10 = $28, which is greater than the price, he will exit theindustry in the long run. Since fixed cost is $30, average variable cost is ($280 - $30)/10 = $25, which is less than price, so Bob won’t shut down in the short run.6. Here’s the table showing costs, revenues, and profits:a. The firm should produce 5 or 6 units to maximize profit.b. Marginal revenue and marginal cost are graphed in Figure 3. The curves cross at aquantity between 5 and 6 units, yielding the same answer as in part (a).c. This industry is competitive since marginal revenue is the same for each quantity. Theindustry is not in long-run equilibrium, since profit is positive.Figure 37. a. Figure 4 shows the short-run effect of declining demand for beef. The shift of theindustry demand curve from D1 to D2 reduces the quantity from Q1 to Q2 and reduces theprice from P1 to P2. This affects the firm, reducing its quantity from q1 to q2. Before thedecline in the price, the firm was making zero profits; afterwards, profits are negative, asaverage total cost exceeds price.Figure 4b. Figure 5 shows the long-run effect of declining demand for beef. Since firms were losingmoney in the short run, some firms leave the industry. This shifts the supply curve fromS1 to S3. The shift of the supply curve is just enough to increase the price back to itsoriginal level, P1. As a result, industry output falls still further, to Q3. For firms thatremain in the industry, the rise in the price to P1 returns them to their original situation,producing quantity q1 and earning zero profits.Figure 58. Figure 6 shows that although high prices cause an industry to expand, entry into the industryeventually returns prices to the point of minimum average total cost. In the figure, the industry is originally in long-run equilibrium. The industry produces output Q1, where supply curve S1intersects demand curve D1, and the price is P1. At this point the typical firm produces output q1.Since price equals average total cost at that point, the firm makes zero economic profit.Now suppose an increase in demand occurs, with the demand curve shifting to D2. This causes "high prices" in the industry, as the price rises to P2. It also causes the industry to increase output to Q2. With the higher price, the typical firm increases its output from q1 to q2, and now makes positive profits, since price exceeds average total cost.However, the positive profits that firms earn encourage other firms to enter the industry. Their entry, "an expansion in an industry," leads the supply curve to shift to S3. The new equilibrium reduces the price back to P1, "bringing an end to high prices and manufacturers' prosperity," since now firms produce q1 and earn zero profit again. The only long-lasting effect is that industryoutput is Q3, a higher level than originally.Figure 69. a. Figure 7 shows the typical firm in the industry, with average total cost ATC1, marginal costMC1, and price P1.b. The new process reduces Hi-Tech’s marginal cost to MC2 and its average total cost to ATC2,but the price remains at P1 since other firms cannot use the new process. Thus Hi-Techearns positive profits.c. When the patent expires and other firms are free to use the technology, all firms’average-total-cost curves decline to ATC2, so the market price falls to P3 and firms earn noprofits.Figure 710. The rise in the price of petroleum increases production costs for individual firms and thus shifts theindustry supply curve up, as shown in Figure 8. The typical firm's initial marginal-cost curve is MC1 and its average-total-cost curve is ATC1. In the initial equilibrium, the industry supply curve, S1, intersects the demand curve at price P1, which is equal to the minimum average total cost of the typical firm. Thus the typical firm earns no economic profit.The increase in the price of oil shifts the typical firm's cost curves up to MC2 and ATC2, and shifts the industry supply curve up to S2. The equilibrium price rises from P1 to P2, but the price does not increase by as much as the increase in marginal cost for the firm. As a result, price is less than average total cost for the firm, so profits are negative.In the long run, the negative profits lead some firms to exit the industry. As they do so, theindustry-supply curve shifts to the left. This continues until the price rises to equal the minimum point on the firm's average-total-cost curve. The long-run equilibrium occurs with supply curve S3, equilibrium price P3, industry output Q3, and firm's output q3. Thus, in the long run, profits arezero again and there are fewer firms in the industry.Figure 811. a. Figure 9 illustrates the situation in the U.S. textile industry. With no international trade,the market is in long-run equilibrium. Supply intersects demand at quantity Q1 and price$30, with a typical firm producing output q1.Figure 9b. The effect of imports at $25 is that the market supply curve follows the old supply curve upto a price of $25, then becomes horizontal at that price. As a result, demand exceedsdomestic supply, so the country imports textiles from other countries. The typicaldomestic firm now reduces its output from q1 to q2, incurring losses, since the large fixedcosts imply that average total cost will be much higher than the price.c. In the long run, domestic firms will be unable to compete with foreign firms because theircosts are too high. All the domestic firms will exit the industry and other countries willsupply enough to satisfy the entire domestic demand.12. a. Figure 10 shows the current equilibrium in the market for pretzels. The supply curve, S1,intersects the demand curve at price P1. Each stand produces quantity q1 of pretzels, sothe total number of pretzels produced is 1,000 x q1. Stands earn zero profit, since priceequals average total cost.b. If the city government restricts the number of pretzel stands to 800, the industry-supplycurve shifts to S2. The market price rises to P2, and individual firms produce output q2.Industry output is now 800 x q2. Now the price exceeds average total cost, so each firm ismaking a positive profit. Without restrictions on the market, this would induce other firmsto enter the market, but they cannot, since the government has limited the number oflicenses.c. The city could charge a license fee for the licenses. Since it is a lump-sum fee for thelicense, not based on the quantity of sales, such a tax has no effect on marginal cost, sowon't affect the firm's output. It will, however, reduce the firm's profits. As long as thefirm is left with a zero or positive profit, it will continue to operate. So the license fee thatbrings the most money to the city is to charge each firm the amount (P2 - ATC2)q2, theamount of the firm's profit.Figure 1013. a. Figure 11 illustrates the gold market (industry) and a representative gold mine (firm).The demand curve, D1, intersects the supply curve at industry quantity Q1 and price P1.Since the industry is in long-run equilibrium, the price equals the minimum point on therepresentative firm's average total cost curve, so the firm produces output q1 and makeszero profit.b. The increase in jewelry demand leads to an increase in the demand for gold, shifting thedemand curve to D2. In the short run, the price rises to P2, industry output rises to Q2,and the representative firm's output rises to q2. Since price now exceeds average totalcost, the representative firm now earns positive profits.c. Since gold mines are earning positive economic profits, over time other firms will enter theindustry. This will shift the supply curve to the right, reducing the price below P2. Butit's unlikely that the price will fall all the way back to P1, since gold is in short supply.Costs for new firms are likely to be higher than for older firms, since they'll have to discovernew gold sources. So it's likely that the long-run supply curve in the gold industry isupward sloping. That means the long-run equilibrium price will be higher than it wasinitially.Figure 1114. a. Figure 12 shows cost curves for a California refiner and a non-California refiner. Since theCalifornia refiner has access to lower-cost oil, its costs are lower.Figure 12b. In long-run equilibrium, the price is determined by the costs of non-California refiners,since California refiners cannot supply the entire market. The market price will equal theminimum average total cost of the other refiners; they will thus earn zero profits. SinceCalifornia refiners have lower costs, they will earn positive profits, equal to (P* - ATC C) xQ C.c. Yes, there is a subsidy to California refiners that is not passed on to consumers. Thesubsidy accounts for the long-run profits of the California refiners. It arises simplybecause the oil cannot be exported.。
曼昆经济学习题解答
曼昆经济学习题解答Ch5 经济增长2⼀、名词解释劳动效率劳动扩⼤型技术进步内⽣增长理论⼆、选择题1．在有⼈⼝增长和技术进步的索洛模型中，稳定状态时每个效率⼯⼈的产出增长率等于：（）A．0 B．技术增长率gC．⼈⼝增长率n＋技术增长率g D．储蓄率s2．在有⼈⼝增长和技术进步的索洛模型中，稳定状态时每个⼯⼈的产出增长率等于：（）A．0 B．技术增长率gC．⼈⼝增长率n＋技术增长率g D．储蓄率s3．在⼈⼝增长⽐率为n和劳动扩⼤型技术进步⽐率为g的索洛模型中，每个效率⼯⼈的资本存量变化等于：（）A．sf(k) + (d + n + g)k B．sf(k) + (d - n - g)kC．sf(k) - (d + n + g)k D．sf(k) - (d - n - g)k4．下列可以⿎励技术进步的是（）A．新产品实⾏专利制度B．对研发的税收激励C．对研发的政府补贴D．以上都是5．索洛模型表明⾼⼈⼝增长率的国家将会有（）：A．较低的稳定状态⼈均产出⽔平B．较低的稳定状态⼈均产出增长率C．A和B D．较⾼的稳定状态⼈均产出增长率三、问答题1．政府政策为医学研究提供资⾦是⼀个经常被争论的问题。
a.运⽤外部性，社会收益和私⼈收益的概念，讨论政府为什么应该或者不应该为医学研究提供资⾦。
政府怎样才能⿎励私营公司增加研究开⽀？b.如果政府觉得需要对医学研究投⼊更⼤的资⾦，你认为政府是直接投资研究项⽬还是对投资这些研究私营公司采⽤激励政策更好？你认为这两个计划分别会对药品⽣产所产⽣的费⽤发⽣怎样的影响？2．⽐较两部门内⽣增长模型和索洛模型。
两个模型的相同之处是什么？两个模型的假设有不同？你觉得哪个更实际？请解释。
3．在索洛模型中，谈谈技术进步、资本存量的增长、⼈⼝的增长对稳定状态的⼈均收⼊增长率的影响？4．为了确定⼀个经济的资本⼤于还是⼩于黄⾦规则稳定状态，你需要什么数据？5．决策者可以如何影响⼀国的储蓄率？6．过去40年间⽣产率的增长率发⽣了什么变动？你如何解释这种现象、7．内⽣增长理论如何在没有外⽣技术进步的假设的情况下解释长期增长？这种解释与索洛模型有什么不同？8．证明下列有关⼈⼝增长与技术进步时稳定状态的每⼀种表述。
经济学原理曼昆课后答案chapter3
Problems and Applications1.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 potatoes. Withlimited time at his disposal, producing a pound of meat means he gives up theopportunity to produce two pounds of potatoes. Similarly, the rancher’s opportunity cost of producing one pound of meat is 1/8 pound of potatoes because for everyhour of work, she can produce one pound of meat or 1/8 pound of potatoes. Withlimited time at her disposal, producing a pound of meat means she gives up theopportunity to produce 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, sothe production 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.Workers needed to make:One Car One Ton of Grain U.S.1/41/10Japan1/41/5b.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, theopportunity cost 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, theopportunity 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:Opportunity Cost of:1 Car (in terms of tons ofgrain given up)1 Ton of Grain (in termsof cars given up)U.S. 2 1/22/5Japan 1 1/44/5d.Neither country has an absolute advantage in producing cars, since they’reequally productive (the same output per worker); the U.S. has an absoluteadvantage 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 termsof cars 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).Japan would produce 200 million cars (50 million workers times 4 cars each)and 250 million tons of grain (50 million workers times 5 tons each).g.From any situation with no trade, in which each country is producing somecars and some grain, suppose the U.S. changed 1 worker from producingcars to producing grain. That worker would produce 4 fewer cars and 10additional tons of grain. Then suppose the U.S. offers to trade 7 tons ofgrain to Japan for 4 cars. The U.S. will do this because it values 4 cars at 10tons of grain, so it will be better off if the trade goes through. SupposeJapan changes 1 worker from producing grain to producing cars. Thatworker would produce 4 more cars and 5 fewer tons of grain. Japan willtake the trade because it values 4 cars at 5 tons of grain, so it will be betteroff. With the trade and the change of 1 worker in both the U.S. and Japan,each country gets the same amount of cars as before and both get additionaltons of grain (3 for the U.S. and 2 for Japan). Thus by trading and changingtheir production, both countries 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 apizza is 2/3 gallons of root beer, since she could brew 2/3 of a gallon in thetime (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 makingpizza.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 bothroommates better off is 2/3 gallons of root beer. If the price were higherthan that, then Kris would prefer making her own pizza (at an opportunitycost of 2/3 gallons of root beer) rather than trading for pizza that Pat makes.The lowest price of pizza in terms of root beer that will make bothroommates 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 1/2gallon of root beer instead of making a pizza) rather than trading for rootbeer 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 opportunitycosts are the reciprocals of each other.b.See Figure 3-4. If all 10 million workers produce two cars each, theyproduce a total of 20 million cars, which is the vertical intercept of theproduction possibilities frontier. If all 10 million workers produce 30 bushelsof wheat each, they produce a total of 300 million bushels, which is thehorizontal intercept of the production possibilities frontier. Since thetradeoff between cars and wheat is always the same, the productionpossibilities frontier is a straight 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 continuesto consume 10 million cars, then Canada will need to produce a total of 20million cars. So Canada will be producing at the vertical intercept of theproduction possibilities frontier. But if Canada gets 20 bushels of wheat percar, it will be able to consume 200 million bushels of wheat, along with the10 million cars. This is shown as point B in the figure. Canada should acceptthe deal because it gets the same number of cars and 50 million morebushes of wheat.Figure 3-46.Though the professor could do both writing and data collection faster than thestudent (that is, he has an absolute advantage in both), his time is limited. If theprofessor’s comparative advantage is in writing, it makes sense for him to pay astudent 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 (50vs. 40). Scottish workers have an absolute advantage over English workersin producing sweaters, since Scottish workers produce more sweaters perhour (2 vs. 1). Comparative advantage runs the same way. Englishworkers, who have an opportunity cost of 1/50 sweaters per scone (1sweater per hour divided by 50 scones per hour), have a comparativeadvantage in scone production over Scottish workers, who have anopportunity cost of 1/20 sweater per scone (2 sweaters per hour divided by40 scones per hour). Scottish workers, who have an opportunity cost of 20scones per sweater (40 scones per hour divided by 2 sweaters per hour),have a comparative advantage in sweater production over English workers,who have an opportunity cost of 50 scones per sweater (50 scones per hourdivided by 1 sweater 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 between20 and 50 scones per sweater will benefit both countries, as they’ll be gettingthe traded good at a lower price than their opportunity cost of producing thegood in 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 wouldbe higher than before (40 scones per sweater, instead of 20 scones persweater before). But there are still gains from trade since England has ahigher opportunity 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. Since the rancher’sopportunity cost of producing potatoes is 8 pounds of meat, the farmer stillhas a comparative advantage in producing potatoes and the rancher still hasa comparative advantage in producing meat.b.Now the farmer won’t be willing to trade 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 hewould then 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 pricein Chicago 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 ofwhite socks, while the opportunity cost of producing a pair of red socks inBoston is 1 pair of white socks. Boston has a comparative advantage inproducing white socks, since the opportunity cost of producing a pair ofwhite socks in Boston is 1 pair of red socks, while the opportunity cost ofproducing a 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 hasthe comparative advantage in white socks, while Chicago produces red socksfor export, 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 whitesocks, Boston will choose to produce its own red socks (at a cost of 1 pair ofred socks per pair of white socks) instead of buying them from Chicago. Ata price higher than 2 pairs of red socks per pair of white socks, Chicago willchoose to produce its own white socks (at a cost of 2 pairs of red socks perpair of white socks) 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 lowerin France than in Germany. Though Germany produces all goods with lesslabor, that labor is more valuable. So the cost of production, in terms ofopportunity cost, 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’snecessary is 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 onegood or activity in terms of another. If you have a comparative advantagein one thing, 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 tradesbased on comparative advantage. If both sides didn’t benefit, trades wouldnever occur.。
曼昆经济学原理课后答案第十三章生产成本
1．企业总收益、利润和总成本之间的关系是什么?答：企业利润＝总收益－总成本2．举出一个会计师不算作成本的机会成本的例子。
为什么会计师不考虑这种成本?答：企业家花时间和精力经营管理企业，他的机会成本是从事其他工作所能赚到的工资。
这种机会成本会计师不记作成本。
因为会计师分析经营活动的依据是货币的流人和流出，隐性机会成本不引起企业的货币流动。
因此，会计师不衡量它。
3．什么是边际产量，边际产量递减意味着什么?答：边际产量是增加一单位投入所引起的产量的增加。
如果出现边际产量递减，则意味着该企业的生产设备已经得到充分利用，只有增加工人才能生产更多的产品。
但新工人不得不在拥挤的条件下工作，而且可能不得不等待使用设备。
4．画出表示劳动的边际产量递减的生产函数。
画出相关的总成本曲线。
(在这两种情况下，都要标明坐标轴代表什么。
)解释你所画出的两个曲线的形状。
答：生产函数表示雇佣的工人数量和生产量之间的关系。
随着工人数量增加，生产函数变得增加，生产函数73变得平坦，这反映了边际产量递减。
由于边际产量递减，边际成本递增，随着产量增加，总成本曲线变得较为陡峭。
图13－1 劳动的边际产量递减的生产函数图13－2 总成本曲线5．叙述总成本、平均总成本和边际成本的定义。
它们之间的关系是怎样的?答：总成本是指企业购买生产投入支付的量。
平均总成本是总成本除以产量。
边际成本指额外－单位产量所引起的总成本的增加。
平均总成本＝总成本/产量边际成本＝总成本变动量/产量变动量6．画出一个典型企业的边际成本和平均总成本曲线。
解释为什么这些曲线的形状是这样，以及为什么在那一点相交。
答：74图13－3 典型企业的边际成本和平均总成本典型企业的边际成本曲线呈U 型。
因为企业在刚开始时，生产能力有剩余，增加一单位的投入量，边际产量会高于前一单位的投入，这样就出现一段边际成本下降。
生产能力全部被利用之后，再增加边际投入，就会出现边际产量递减，边际成本递增。
曼昆经济学原理11章--15章课后答案
第十一章公共物品和共有资源复习题1．解释一种物品有“排他性”的含义。
解释一种物品有“竞争性”的含义。
比萨饼有排他性吗?有竞争性吗?答：一种物品具有“排他性”是指可以阻止一个人使用一种物品时该物品的特性。
一种物品有竞争性是指一个人使用一种物品减少其他人使用该物品的特性。
比萨饼有排他性，只要不卖给某人比萨饼就可以阻止他使用。
比萨饼也有竞争性，一个人多吃一块比萨饼，会使其他人少享受一块。
2．给公共物品下定义并举出一个例子。
私人市场本身能提供这种物品吗?并解释之。
答：公共物品是既无排他性又无竞争性的物品，私人市场本身不能提供这种物品。
公共物品没有排他性，因此，无法对公共物品的使用者收费，在私人提供这种物品时就存在搭便车的激励，从而使私人提供者无利可图。
3．什么是公共物品的成本一收益分析?为什么它是重要的?进行这种分析困难吗?答：公共物品的成本一收益分析是提供一种公共物品的社会成本和社会收益比较的研究。
只有比较提供一种公共物品的成本与收益，政府才能决定是否值得提供这种公共物品。
公共物品的成本一收益分析是一项艰苦的工作。
因为所有的人都可以免费使用一种公共物品，没有判断这种公共物品价值的价格。
简单地问人们，他们对一种公共物品的评价是多少是不可靠的。
那些受益于该公共物品的人有夸大他们的利益的激励。
那些受害于该公共物品的人有夸大他们成本的激励。
4．给共有资源下定义并举出一个例子。
没有政府干预，人们使用这种物品会太多还是太少?为什么?答：共有资源是有竞争性但无排他性的物品。
没有政府干预，人们使用这种物品会太多。
因为不能向使用共有资源的人收费，而且，一个人对共有资源的使用会减少其他人的使用，所以，共有资源往往被过度使用。
问题与应用1．本书认为公共物品和共有资源都涉及外部性。
A．与公共物品相关的外部性一般是正的还是负的?用例子来回答。
自由市场的公共物品量一般是大于还是小于有效率的数量?答：与公共物品相关的外部性一般是负的。
曼昆经济学原理答案全解1
第一篇导言第一章经济学十大原理复习题1．列举三个你在生活中面临的重要权衡取舍的例子。
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。
5．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活动，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．市场中的那只“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”指引着千百万个体决策者在大多数情况下使社会福利趋向最大化。
7．解释市场失灵的两个主要原因，并各举出一个例子。
答：市场失灵的主要原因是外部性和市场势力。
(完整版)曼昆宏观经济学原理答案
第一篇导言复习题第一章宏观经济学的科学1、解释宏观经济学和微观经济学之间的差距，这两个领域如何相互关联？【答案】微观经济学研究家庭和企业如何作出决策以及这些决策在市场上的相互作用。
微观经济学的中心原理是家庭和企业的最优化——他们在目的和所面临的约束条件下可以让自己的境况更好。
而相对的，宏观经济学研究经济的整体情况，它主要关心总产出、总就业、一般物价水平和国际贸易等问题，以及这些宏观指标的波动趋势与规律。
应该看到，宏观经济学研究的这些宏观经济变量是以经济体系中千千万万个体家庭和企业之间的相互作用所构成的。
因此，微观经济决策总是构成宏观经济模型的基础，宏观经济学必然依靠微观经济基础。
2、为什么经济学家建立模型？【答案】一般来说，模型是对某些具体事物的抽象，经济模型也是如此。
经济模型可以简洁、直接地描述所要研究的经济对象的各种关系。
这样，经济学家可以依赖模型对特定的经济问题进行研究；并且，由于经济实际不可控，而模型是可控的，经济学家可以根据研究需要，合理、科学的调整模型来研究各种经济情况。
另外，经济模型一般是数学模型，而数学是全世界通用的科学语言，使用规范、标准的经济模型也有利于经济学家正确表达自己的研究意图，便于学术交流。
3、什么是市场出清模型？什么时候市场出清的假设是适用的？【答案】市场出清模型就是供给与需求可以在价格机制调整下很快达到均衡的模型。
市场出清模型的前提条件是价格是具有伸缩性的（或弹性）。
但是，我们知道价格具有伸缩性是一个很强的假设，在很多实际情况下，这个假设都是不现实的。
比如：劳动合同会使劳动力价格在一段时期内具有刚性。
因此，我们必须考虑什么情况下价格具有伸缩性是合适的。
现在一般认为，在研究长期问题时，假设价格具有伸缩性是合理的；而在研究短期问题时，最好假设价格具有刚性。
因为，从长期看，价格机制终将发挥作用，使市场供需平衡，即市场出清，而在短期，价格机制因其他因素制约，难以很快使市场出清。
曼昆 经济学原理 第三版 答案 第1篇
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。
5 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。
7 解释市场失灵的两个主要原因，并各举出一个例子。
答：市场失灵的主要原因是外部性和市场势力。
曼昆微观经济学(第三版)课后习题答案
Ch1.绪论一、名词解释二、问答题1.微观经济学研究家庭和企业如何作出决策以及这些这些决策在市场上的相互作用。
微观经济学的中心原理是家庭和企业的最优化——他们在目的和所面临的约束条件下可以让自己的景况更好。
而相对的，宏观经济学研究经济的整体情况，它主要关心总产出、总就业、一般物件水平和国际贸易等问题，以及这些宏观指标的波动趋势与规律。
应该看到，宏观经济学研究的这些宏观经济变量是以经济体系中千千万万个体家庭和企业之间的相互作用所构成的。
因此，微观经济决策总是构成宏观经济模型的基础，宏观经济学必然依靠微观经济基础。
2.一般的，模型是对某些具体事物的抽象，经济模型也是如此。
经济模型可以简洁、直接地描述所要研究的经济对象的各种关系。
这样，经济学家可以依赖模型对特定的经济问题进行研究；并且，由于经济实际不可控，而模型是可控的，经济学家可以根据研究需要，合理、科学的调整模型来研究各种经济情况。
另外，经济模型一般是数学模型，而数学是全世界通用的科学语言，使用规范、标准的经济模型也有利于经济学家正确表达自己的研究意图，便于学术交流。
3.略。
请结合您目前所搜集的最新宏观经济新闻进行讨论。
4.市场出清模型就是供给与需求可以在价格机制调整下很快达到均衡的模型。
市场出清模型的前提条件是价格是具有伸缩性的（或弹性）。
但是，我们知道，价格具有伸缩性是一个很强的假设，在很多实际情况下，这个假设都是不现实的。
比如：劳动合同会使劳动力价格在一段时期内具有刚性。
因此，我们必须考虑什么情况下价格具有伸缩性是合适的。
现在一般地认为，在研究长期问题时，假设价格具有伸缩性是合理的；而在研究短期问题时，最好假设价格具有刚性。
因为，从长期看，价格机制终将发挥作用，使市场供需平衡，即市场出清，而在短期，价格机制因其他因素制约，难以很快使市场出清。
5.一般的，人们认为科学的定义是：一种建立稳定关系的科学的研究方法。
比如：物理学家可以通过实验来收集数据，证明或推翻一个假设。
曼昆《经济学原理(微观经济学分册)》课后习题详解(第1篇)
曼昆《经济学原理（微观经济学分册）》课后习题详解（第1篇）第1篇导言第1章经济学十大原理一、概念题1．稀缺性（scarcity）答：经济学研究的问题和经济物品都是以稀缺性为前提的。
稀缺性指在给定的时间内，相对于人的需求而言，经济资源的供给总是不足的，也就是资源的有用性与有限性。
人类消费各种物品的欲望是无限的，满足这种欲望的物品，有的可以不付出任何代价而随意取得，称之为自由物品，如阳光和空气；但绝大多数物品是不能自由取用的，因为世界上的资源（包括物质资源和人力资源）是有限的，这种有限的、为获取它必须付出某种代价的物品，称为“经济物品”。
正因为稀缺性的客观存在，地球上就存在着资源的有限性和人类的欲望与需求的无限性之间的矛盾。
经济学的一个重要研究任务就是：“研究人们如何进行抉择，以便使用稀缺的或有限的生产性资源（土地、劳动、资本品如机器、技术知识）来生产各种商品，并把它们分配给不同的社会成员进行消费。
”也就是从经济学角度来研究使用有限的资源来生产什么、如何生产和为谁生产的问题。
2．经济学（economics）答：经济学是研究如何将稀缺的资源有效地配置给相互竞争的用途，以使人类的欲望得到最大限度满足的科学。
时下经常见诸国内报刊文献的“现代西方经济学”一词，大多也都在这个意义上使用。
自从凯恩斯的名著《就业、利息和货币通论》于1936年发表之后，西方经济学界对经济学的研究便分为两个部分：微观经济学与宏观经济学。
微观经济学是以单个经济主体（作为消费者的单个家庭或个人，作为生产者的单个厂商或企业，以及单个产品或生产要素市场）为研究对象，研究单个经济主体面对既定的资源约束时如何进行选择的科学。
宏观经济学则以整个国民经济为研究对象，主要着眼于对经济总量的研究。
3．效率（efficiency）答：效率指人们在实践活动中的产出与投入之比值，或者是效益与成本之比值，如果比值大，效率就高；反之，比值小，效率就低。
效率与产出或者收益的大小成正比，而与成本或投入成反比，也就是说，如果想提高效率，必须降低成本或投入，提高收益或产出。
曼昆经济学习题解答
Ch04 经济增长1一、名词解释索洛增长模型稳定状态资本的黄金规则水平二、选择题1．下面关于资本的边际产量MPK的哪些说法是错误的（）A．MPK = f(k + 1) - f(k) B．MPK随K增加而减少C．当资本量低时，MPK很小D．MPK等于生产函数y = f(k)的斜率。
2．如果资本可平均使用50年，那么折旧率为（）：A．50％，或每年0.5 B．0.5％，或每年0.005C．2％，或每年0.02 D．0.02％，或0.00023．如果生产函数Y = F(K, L)为规模收益不变，那么（）：A．F(zK, zL) = zY B．F(K/L, 1) = Y/LC．y = f(k), y为每个工人的产出，k为每个工人的资本量D．以上都对4．如果y = k1/2, s = 0.4，折旧率d = 20％，那么稳定状态的人均资本水平为（）A．4 B．8 C．2 D．25．资本的黄金规则水平是（）的最大化A．人均消费水平B．人均产出C．人均消费增长率D．人均产出增长率6．一个初始处于稳定状态的经济提高储蓄率，到达新的稳定状态后（）A．人均产出增长更快于以前B．人均产出水平高于以前C．人均资本不变D．以上都对三、问答题1.为什么一个经济决策者会选择黄金规则的资本水平？2.决策者会选择其资本高于黄金规则稳定状态的稳定状态吗？会选择其资本低于黄金规则稳定状态的稳定状态吗？解释之。
3.1983年的《总统经济报告》包括了下面这样一段话：“把较大比例的国民产出用于投资将有助于迅速恢复生产率增长，并提高生活水平。
”你同意这种主张吗？并解释之。
4.在索洛模型中，储蓄率如何影响稳定状态的收入水平？它如何影响稳定状态的增长率？5.一种消费函数的观点是，工人边际消费倾向高，而资本家边际消费倾向低。
为了说明这种观点的含义，假设一个经济所有的工资收入都用于消费，而所有资本收入都用于储蓄。
说明，如果生产要素赚到了自己的边际产量，这个经济就达到了黄金规则的资本水平。
曼昆经济学原理课后答案第十四章竞争市场上的企业
复习题1．竞争企业的含义是什么?答：竞争企业指处于竞争市场上的企业，任何一个竞争企业都是价格的接受者。
2 5 553 5 38.334 5 305 5 256 5 21.677 5 19.298 5 17.509 5 16.1110 5 15产量（成本单位：美元）12345实用文档67企业A 60708090100 110 120企业B 112439567596119实用文档企业C2134496685106129产量（成本单位：美元）1 2 3 4 5 6 7企业A 60 35 27 22.5 20 18 17企业B 11 12 13 14 15 16 17企业C 21 17 16 16.5 17 18 18.4812．解释企业收益与企业利润的差别。
企业使什么最大化？答：企业的总收益等于单位销售数量乘以其价格，即企业销售其产品所得到的货币量。
企业利润是总收益和总成本的差额。
企业使利润最大化。
实用文档3．画出一个典型企业的成本曲线。
解释在某一既定价格时，企业应如何选择利润最大化的产量水平。
在该产量水平时，在你的图形中标明企业的总收益及总成本答：竞争企业在某一既定价格时，利润最大化的产量水平Q 是在边际成本曲线和价格水平曲线的相交之处。
因为如果企业选择产量Q1，Q1<Q，MC<MR，即企业增加一单位产量所带来的边际收益大于边际成本。
于是，企业会增加产量以提高利润。
如果企业选择产量Q2(Q2>Q)，MC>MR，即企业再增加一单位产量所带来的边际收益小于边际成本。
于是，企业可以通过减少产量以提高利润。
图14－1 典型企业的成本曲线4．在什么条件下企业将暂停营业？解释原因。
答：如果物品的价格低于生产的平均成本，企业选择停止营业。
在短期内，固定成本是沉没成本，在此决策中不考虑。
作出这一决策的原因很简单：在选择生产时，企业比较普通一单位产量所得到的价格与生产这一单位实用文档必定引起的平均可变成本。
曼昆《经济学原理》答案
第一篇导言第一章经济学十大原理复习题1．列举三个你在生活中面临的重要权衡取舍的例子。
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。
8．为什么生产率是重要的?答：因为一国的生活水平取决于它生产物品与劳务的能力，而对这种能力的最重要的衡量度就是生产率。
生产率越高，一国生产的物品与劳务量就越多。
9．什么是通货膨胀，什么引起了通货膨胀?答：通货膨胀是流通中货币量的增加而造成的货币贬值，由此产生经济生活中价格总水平上升。
货币量增长引起了通货膨胀。
10．短期中通货膨胀与失业如何相关?答：短期中通货膨胀与失业之间存在着权衡取舍，这是由于某些价格调整缓慢造成的。
政府为了抑制通货膨胀会减少流通中的货币量，人们可用于支出的货币数量减少了，但是商品价格在短期内是粘性的，仍居高不下，于是社会消费的商品和劳务量减少，消费量减少又引起企业解雇工人。
在短期内，对通货膨胀的抑制增加了失业量。
问题与应用3．你正计划用星期六去从事业余工作，但一个朋友请你去滑雪。
去滑雪的真实成本是什么?现在假设你已计划这天在图书馆学习，这种情况下去滑雪的成本是什么?并解释之。
答：去滑雪的真实成本是周六打工所能赚到的工资，我本可以利用这段时间去工作。
如果我本计划这天在图书馆学习，那么去滑雪的成本是在这段时间里我可以获得的知识。
5．你管理的公司在开发一种新产品过程中已经投资500万美元，但开发工作还远远没有完成。
在最近的一次会议上，你的销售人员报告说，竞争性产品的进入使你们新产品的预期销售额减少为300万美元。
经济学基础(曼昆)课后习题答案
第一章经济学十大原理一、为每个关键术语选择一个定义关键术语定义--------------稀缺性1、在社会成员中平等地分配利益的特征--------------经济学2、市场不能有效的配置资源的状况--------------效率3、有限的资源和无限的欲望--------------平等4、一个工人一小时所生产的物品与劳务量--------------理性5、市场上只有一个买者的情况--------------时机本钱6、利己的市场参与者可以不知不觉的使整体社会福利最大化的原理--------------边际变动7、社会从其稀缺资源中得到最多东西的特性--------------鼓励8、社会和企业在市场上的相互交易决定资源配置的经济--------------市场经济9、经济活动的波动--------------产权10、当一个人的行为对旁观者有影响时的情况--------------“看不见的手〞11、物价总水平的上升--------------市场失灵12、对现行方案的增量调整--------------外部性13、研究社会如何管理其稀缺资源--------------市场势力14、得到某种东西所放弃的东西--------------垄断15、一个人或一群人不适当的影响市场价格的能力--------------生产率16、某种引起人行动的东西--------------通货膨胀17、一个人拥有并使用稀缺资源的能力--------------经济周期18、为了到达目标而尽可能系统性的做到最好二、判断正误--------------1、当政府用税收和福利再分配收入时，经济变得更有效率。
-------------2、当经济学家说“天下没有免费的午餐〞时，他们是指所有经济决策都涉及权衡取舍。
-------------3、亚当斯密的“看不见的手〞的概念描述了公司经营如何像一只“看不见的手〞伸到消费者的钱包中。
《经济学原理·曼昆·第三版》第14章
When MR > MC —— increase Q When MR < MC —— decrease Q When MR = MC ——Profit is maximized.
The Marginal-Cost Curve and the Firm’s Supply Decision...
Costs and Revenue
市场上有许多买者和许多卖者
各个卖者提供的物品大体上是相同的
企业可以自由地进入或退出市场
14.1.2 竞争企业的收益 The Revenue Of A Competitive Firm
竞争市场上的企业与经济中大 多数其他企业一样，努力使利 润最大化，利润等于总收益减 总成本。为了说明如何做到这 一点，我们首先考虑竞争企业 的收益。为了使事情具体化， 我们考虑一个特定企业：斯密 的家庭奶牛场。
Costs and Revenue The firm maximizes profit by producing the quantity at which marginal cost equals marginal revenue.
MC
ATC P=MR1 MC1 P = AR = MR AVC
0
Q1
The Firm’s Short-Run Decision to Shut Down
The firm shuts down if the revenue it gets from producing is less than the variable cost of production.
Shut down if TR < VC
14.1 什么是竞争市场 What is A Competitive Market?