黑龙江省大庆实验中学2020┄2021学年高二下学期第一次网上周测试题2.15英语

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黑龙江省大庆实验中学2020-2021学年度高三第一次线上教学质量检测英语试题参考答案

黑龙江省大庆实验中学2020-2021学年度高三第一次线上教学质量检测英语试题参考答案

大庆实验中学2021年实验三部第一次线上教学质量检测高三英语学科试题说明:1. 本套试题答题时间100分钟,总分为150分。

2. 本套试题共分三部分:阅读理解、语言知识运用、写作。

第一部分阅读理解(共两节,满分40分)第一节(共15小题;每小题2分,满分30分)阅读下列短文,从每题所给的四个选项(A、B、C、D) 中,选出最佳选项。

AKings CampsAbout Our CampsKings Camps is part of the Kings Active Foundation and is devoted to helping young people reach their potential. We provide sports camps and summer camps at over 40 places across the UK for children aged 4-17. We bring together the very best aspects of sports and holiday clubs to provide friendship, fun and exciting adventures for young people from the UK and around the world.Why Choose Kings Camps* Creative, inspiring camps: We have a strong belief that sport has an important role to play in a happy childhood and our not-for-profit status enables us to provide some places and invest in new and creative ways to inspire.* Learn important life skills: Kings Camps equip children with important life skills and understanding that being active is vital to health and well-being.* International students are welcome: We welcome children from outside of the UK who will make friends here by communicating with kids from different backgrounds, but we do request that they at least understand English to guarantee their safety and that of others, and of course their enjoyment.CommentsRyan has enjoyed every aspect. When we’ve asked about his day, he’s said it was “amazing and fantastic”. All the staff are extremely friendly, enthusiastic and have a true belief in what they are doing.-Tracy Lee Fantastic & friendly staff! It’s an action-packed week of multiple sports. My sweetheart made new friends, overcame swimming fears & came away more confident too! I cannot recommend it enough!-Kay Court 21.What does Kings Camps aim to do?A. Combine sports and holiday clubs.B. Get kids to diversity.C. Provide adventurous and challenging camps.D. Encourage kids to develop their potential. 22.What’s necessary for international students?A. Awareness of safety.B. Love for outdoor sports.C. Basic English ability.D. Good communicating skills.23.Who probably made the comments?A. Parents.B. Teachers.C. Campers.D. Staff.答案:DCABMy mom is about to have a spinal (脊柱的) operation. The operation is relatively minor, but does carry a risk of paralysis. Friends and family have reacted to this news by taking in such pessimistic terms that Mom has come to label this kind of talk as “psychological theft”. It occurs when other people increase your anxiety rather than provide comfort.Last week Mom went to the post office and ran into Geoff who works for the local school. “How are you?” he asked. “Not great,” she replied. “I’ve been having some trouble with my back and I’m going to need an operation.” “Oh, the back is the most dangerous place to operate on!” he responded. “My mom had that and she was in terrible pain. Make sure you get all your affairs in order before you go under the knife—it takes months to get over it!” Geoff’s intention had been benign(美好的). He’d given his own mother’s story to show sympathy. However, Mom only heard pain, danger, knife, and months.In the past few weeks, Mom’s mates and colleagues have told her stories about how their Auntie Trisha, who had just received an operation, was left speechless after hearing that she required a rapid follow-up operation; and how their neighbor, who had only a minor operation, never walked again.It’s really not that difficult to think of alternative things they could have said that would be equally true, but more beneficial to patients to h ear. “The specialists in our hospitals are among the best in the world. It’s amazing what they can do these days!”—that’s a good one. “You’re going to feel much better afterward.”—that’s another.I’m not suggesting patients should be sheltered from the reality of the risks they’re taking. But if the decision to have an operation can’t really be avoided, what’s the purpose of underlining the drawbacks? It’s just common sense to say: “Get well soon, and how can I help?24. What does “psychological theft” in Paragraph 1 refer to?A. The negative comments.B. Psychological disorder.C. The comforting words.D. Physical disability.25. How might the author’s mom have felt after hearing what Geoff said?A. SympatheticB. RelievedC. MovedD. Worried26. How did the author explain his idea in the text?A. By using examplesB. By analyzing causesC. By following time order.D. By discussing research findings27. What lesson does the author want to teach us?A. Treat patients with adoration.B. Communicate more with other patientsC. Be well-prepared for unavoidable operations.D. Find an appropriate way to comfort patients.答案:ADADCThe fashion industry urgently needs to transition to a “slow” fashion model to reduce its heavy environmental damage, according to researchers at Aalto University, Finland.The environmental impact of fashion’s global supply chain continues to rise, they say in a paper published in the journal Nature. The industry currently produces over 92 million tons of waste and consumes 79 trillion liters of water per year. It causes around 10 percent of the world’s greenhouse gas emissions (排放) and is also a high source chemical pollution. Developing countries tend to suffer most from the industry, since production often occurs there.The fashion industry is also projected to grow significantly in the coming decades. Fashion brands are already producing almost twice the amount of clothing they did 20 years ago, while global consumption of textiles (纺织品) is projected to increase by over 60 percent to 102 million tons by 2030, the paper said.“It’s critical that we, as consumers, accept that these cheap clothes are not possible if the environmental impacts are really all taken care of,” said Dr. Kirsi Niinimaiki. “In the future we should produce less. If we buy less, there will be less waste.”People in the UK buy more clothes per person than any other country in Europe. Last year, a cross-party parliamentary committee in the UK called on the government to add a 1 penny “producer responsibility charge” on each item of clothing to pay for better collection and recycling of unwanted clothes.Dr. Mark Sumner, a lecturer in sustainability in retail and fashion at the University of Leeds, said that the paper gave a good overview of the material aspects of the industry, but missed the opportunity to highlight efforts by more responsible brands to address these environmental problems.“There are definitely success stories out there in terms of what industry has done,” said Sumner, adding that not enough brands are using that best practice. He also said it’s important not to see “slow” fashion as the only answer.28.What is one of the major concerns about the fast fashion industry?A.Emission of greenhouse gases. B.Waste of clothing materials.C.A sharp increase in diseases. D.A fierce competition in fashion.29.What is the purpose of paragraph 5?A.To support the idea of less clothing production.B.To illustrate how fast fashion industry develops.C.To prove that British people buy more clothes.D.To show a measure to reduce clothes purchase. 30.What do Dr. Mark Sumner’s words imply?A.“Slow” fashion is a must. B.Consumers should buy less.C.A new approach is needed. D.Industry has done well enough.31.What does the text mainly talk about?A.Future of the fashion industry. B.Needs to deal with fast fashion.C.Reduction of clothing production. D.Changes to sustainability in fashion.答案:ADCBDLikely to suffer from loss of memory from time to time? Smart cameras can now remind you.Khai Truong at the University of Toronto in Canada and his colleagues have created a smartphone app that records interactions with household objects. The system involves barcode-like(像条形码的) markers that the user sticks to objects whose use they would like to track.With the smartphone worn around your neck, the app automatically records a short video clip(片段) when a marked object comes into view. “The user is able to look through the application and see the last time they interacted with it,” says Truong. The app can help people track the state of objects—such as whether they locked a door or switched a light off—as well as routine actions. At present, it successfully records about 75 percent of interactions, but only works for fixed objects.A similar but separate system can solve the problem. E. Akin Sisbot and Jonathan Connell at IBM Research in New York have invented a ceiling-mounted(安装在天花板上的) camera that monitors objects and people. It continuously watches an area, such as a tabletop in your home, tracking the placement of objects in relation to one another. It also remembers who first brought an object into the field of view as well as if anyone moved it afterwards. When asked, “Where is my wallet?” the system might respond, “It is next to the vase, un der the magazines.”The camera could also be used in factories or operating theaters to track vital tools, says Sisbot. For now, the camera uses a depth sensor to spot things. It is limited to detecting objects thicker than 3 centimeters, meaning that it has trouble with thin objects such as a closed laptop placed flat on a table.The accuracy of such smart camera systems may need to improve before they are widely adopted. “You’ve got to trust the technology for it to be of any comfort or reassurance” says Geoffrey Ward at the University of Essex in the UK.32.How does the smartphone app mentioned in paragraph 2 work?A. By switching off electricity automatically.B. By scanning barcodes of household objects.C. By recording the movement of marked objects.D. By informing owners of potential dangers.33. What is the limitation of the ceiling-mounted camera?A. It is unlikely to make a sound.B. It is unable to recognize movable objects.C. It fails to find objects thinner than 3 centimetres.D. It hardly senses objects without barcode-like makers.34. What’s Geoffrey Ward’s attitude towards the smart camera systems?A. ConcernedB. SupportiveC. SkepticalD. Ambiguous35. What’s the best title for the text?A. New Smartphones Make Life EasierB. Camera Designers Face New ChallengesC. Smart Cameras Help Increase Home SecurityD. New Systems Help People with Memory Problems答案:CCBD第二节(共5小题;每小题2分,满分10分)根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。

黑龙江省大庆实验中学2020-2021学年高二寒假线上教学质量检英语试题(pdf版,无答案)

黑龙江省大庆实验中学2020-2021学年高二寒假线上教学质量检英语试题(pdf版,无答案)

B. Shock Wave.
C. Roaring Rapids.
D. The Viper.
2. How much should a young couple pay for one day with parking if they book over the Internet?
A. $64.
B. $73.
A. She got the right instructions from the doctor.
B. She got experience in helping raise six children.
C. She once had croup and remembered how she was treated.
Minnie May did not take kindly to it, but Anne had not brought up three pairs of twins for nothing. Down it
went, not only once, but many times during the long, worrying night when the two little girls worked patiently over
Shock Wave. This wonderful roller coaster turns riders upside down six times. Wow, what a thrill!
Roaring Rapids. Travel on a boat, go high in the sky and then go down fast for an exciting landing.

黑龙江省大庆实验中学2020_2021学年高二英语10月月考试题2

黑龙江省大庆实验中学2020_2021学年高二英语10月月考试题2

黑龙江省大庆实验中学2020-2021学年高二英语10月月考试题说明:答题时间120分钟,卷面总分150分I. 听力(共两节,满分20分)第一节(共5小题;每小题1分,满分5分)听下面5段对话。

每段对话后有一个小题,从题中所给的A、B、C三个选项中选出最佳选项,并标在试卷的相应位置。

听完每段对话后,你都有10秒钟的时间来回答有关小题和阅读下一小题。

每段对话仅读一遍。

1. How did Nancy first react to being offered chocolate?A. Surprised.B. Disappointed.C. Happy.2. What do we know about the man?A. He is allergic to cats.B. He had a bad cold on his first day of work.C. He often brings his cat to work.3. What does the man mean?A. He had a lot of help.B. He is hungry now.C. The work is easy for him.4. Why does the man ask the woman to help him paint his bedroom?A. His brother can’t do it.B. The woman is really good at painting.C. His arm is broken.5. Where might the man’s backpack be?A. He is wearing it.B. It’s at school.C. Claire has it.第二节(共15小题;每小题1分,满分15分)听下面5段对话或独白。

每段对话或独白后有几个小题,从题中所给的A、B、C三个选项中选出最佳选项,并标在试卷的相应位置。

2020-2021学年黑龙江省大庆实验中学高二下学期开学考试物理试卷

2020-2021学年黑龙江省大庆实验中学高二下学期开学考试物理试卷

【最新】黑龙江省大庆实验中学高二下学期开学考试物理试卷学校:___________姓名:___________班级:___________考号:___________一、单选题1.在科学发展史上,很多科学家做出了杰出的贡献。

他们在物理学的研究过程中应用了很多科学的思想方法。

下列叙述不正确的是()A.法拉第首先提出用电场线描绘抽象的电场,这是一种形象化的研究方法B.电场强度的表达式E=Fq 和电势差的表达式U=Wq都是利用比值法得到的定义式C.库仑得出库仑定律并用扭秤实验最早测出了元电荷e的数值D.用点电荷来代替实际带电体是采用了理想化物理模型的方法2.在如图所示的电场中,有A、B、C三点。

关于这三点的描述,正确的是()A.B点的电势最高B.A点的场强最大C.C点无电场线,所以场强为零D.将一带正电试探电荷从A点释放,此试探电荷仅在电场力力作用下一定会沿电场线运动到B点3.如图所示,带负电的粒子以速度v从离子源P处射出,若图中匀强磁场范围足够大(方向垂直纸面向里),则带电粒子的可能轨迹是( )A.cB.dC.aD.b4.如图所示,通电导线MN中的电流保持不变,当它在纸面内从a位置绕其一端M转至b位置时,通电导线所受安培力的大小变化情况是( )A.变小B.变大C.不变D.不能确定5.如右图所示,理发用的电吹风机中有电动机和电热丝,电动机带动风叶转动,电热丝给空气加热,得到热风将头发吹干,设电动机的线圈电阻为R1,它与电热丝的电阻R2串联,接到直流电源上,电吹风机两端电压为U,电流为I,消耗的电功率为P,则有A.P<UI B.P=I2(R1+R2) C.P>UI D.P>I2(R1+R2) 6.如图所示,在竖直向上的匀强磁场中,水平固定放置一根通电的长直导线,电流方向垂直纸面向外,a、b、c、d是以直导线为圆心的同一圆周上的四点,在这四点中A.a点磁感应强度最大B.c点磁感应强度最大C.a、c两点磁感应强度相同D.b、d两点磁感应强度相同7.如图所示,MN是一根固定的通电长直导线,电流方向向上,今将一金属线框abcd 放在导线上,让线框的位置偏向导线左边,两者彼此绝缘.当导线中的电流突然增大时,线框整体受力情况为( )A.受力向右B.受力向左C.受力向上D.受力为零8.如图所示,正方形线圈abcd位于纸面内,边长为L,匝数为N,过ab中点和cd中点的连线OO′恰好位于垂直纸面向里的匀强磁场的右边界上,磁感应强度为B,在t时间内磁场的磁感应强度变为0,则线圈中感应电动势大小为()A.BL2B.BL2tC.BL22t D.NBL22t9.如图所示为一个有界的足够大的匀强磁场区域,磁场方向垂直纸面向外,一个不计重力的带正电的粒子以某一速率v垂直磁场方向从O点进入磁场区域,电子进入磁场时速度方向与边界夹角为θ,下列有关说法正确的是()A.若θ一定,速度v越大,粒子在磁场中运动时间越长B.粒子在磁场中运动时间与速度v有关,与角θ大小无关C.粒子在磁场中运动时间与角度θ有关,与速度v无关D.若速度v一定,θ越大,粒子在磁场中运动时间越长10.如图所示,某空间存在正交的匀强磁场和匀强电场,电场方向水平向右,磁场方向垂直纸面向里,带电微粒由a点进入该区域并刚好沿ab直线向上运动,下列说法正确的是( )A.微粒一定做匀速直线运动B.微粒可能带正电C.微粒的电势能一定增加D.微粒的机械能一定减少二、多选题11.如图所示,A、B为两个等量同种点电荷,a、O、b在点电荷A、B的连线上,c、O、d在连线的中垂线上Oa=Ob=Oc=Od,则()A.c、d两点的场强不相同,电势相同B.a、b两点的场强相同,电势也相同C.O点是中垂线上场强最大的点D.O点是A、B连线上电势最低的点12.如图所示电路中,A1和A2是完全相同的灯泡,线圈L电阻可以忽略.下列说法中正确的是()A.合上开关K时,A2先亮,A1后亮,最后一样亮B.合上开关K接通电路时,A1和A2始终一样亮C.断开开关K时,A2立刻熄灭,A1逐渐熄灭D.断开开关K时,A1和A2都逐渐熄灭13.在某次发射科学实验卫星“双星”中,放置了一种磁强计,用于测定地磁场的磁感应强度.磁强计的原理如图所示(背面),电路中有一段金属导体,它的横截面是宽为a、高为b的长方形,放在沿y轴正方向的匀强磁场中,导体中通有沿x轴正方向、大小为I的电流.已知金属导体单位体积中的自由电子数为n,电子电荷量为e.金属导电过程中,自由电子做定向移动可视为匀速运动.测出金属导体前后两个侧面间的电势差为U.则下列说法正确的是()A.后侧面电势高于前侧面B.前侧面电势高于后侧面C.磁感应强度的大小为nebU BI =D.磁感应强度的大小为2nebU BI =14.如图所示,MN是纸面内的一条直线,其所在空间充满与纸面平行的匀强电场或与纸面垂直的匀强磁场(场区都足够大),现有一个重力不计的带电粒子从MN上的O点以水平初速度v0射入场区,下列判断正确的是()A.如果粒子回到MN上时速度增大,则该空间存在的场一定是电场B.如果粒子回到MN上时速度大小不变,则该空间存在的场可能是电场C.若只改变粒子初速度大小,发现粒子再回到MN上所用时间不变,则该空间存在的场一定是磁场D.若只改变粒子的初速度大小,发现粒子再回到MN上时与其所成的锐角夹角不变,则该空间存在的场一定是磁场三、实验题15.某学生用螺旋测微器在测定某一金属丝的直径时,测得的结果如下图所示,则该金属丝的直径d=_______mm.另一位学生用游标尺上标有20等分刻度的游标卡尺测一工件的长度,测得的结果如下图所示,则该工件的长度L=_____cm.16.测量电阻有多种方法(1)若用多用电表欧姆挡测电阻,下列说法中正确的是________A.测量电阻时如果指针偏转过大,应将选择开关拨至倍率较小的挡位,重新调零后测量B.测量电阻时,如果红、黑表笔分别插在负、正插孔,则会影响测量结果C.测量电路中的某个电阻,应该把该电阻与电路断开D.测量阻值不同的电阻时都必须重新调零(2)用以下器材测量待测电阻R x的阻值:A.待测电阻R x,阻值约为200ΩB.电源E,电动势约为3.0v,内阻可忽略不计C.电流表A1,量程为0~10mA,内电阻r1=20ΩD.电流表A2,量程为0~20mA,内电阻r2约为8ΩE.定值电阻R0,阻值R0=80ΩF.滑动变阻器R1,最大阻值为10ΩG.滑动变阻器R2,最大阻值为200ΩH.单刀单掷开关S,导线若干.①为了测量电阻R x,你认为应选择下面的_____图做为实验电路(填“甲”、“乙”或“丙”).②滑动变阻器应该选______;在闭合开关前,滑动变阻器的滑片P应置于____端;(填“a”或“b”)③实验中,需要直接测量的物理量是_________,用已知量和测量量计算R x的表达式是R x=___________.四、填空题17.如图所示,充电后的平行板电容器水平放置,电容为C,极板间距离为d,上极板正中有一小孔。

黑龙江省2020-2021年高二下学期第一次月考化学试卷(实验班)(理科)

黑龙江省2020-2021年高二下学期第一次月考化学试卷(实验班)(理科)

黑龙江省2020-2021年高二下学期第一次月考化学试卷(实验班)(理科)姓名:________ 班级:________ 成绩:________一、单选题 (共20题;共40分)1. (2分) (2018高一下·吉林开学考) 无色的混合气体甲,可能含有NO、CO2、NO2、NH3、N2中的某几种。

将100mL甲气体经过下图实验的处理,结果得到酸性溶液,而几乎无气体剩余。

则甲气体的组成为()A . NH3、NO2、N2B . NH3、NO2、CO2C . NH3、NO、CO2D . NO、CO2、N22. (2分) (2016高一上·宜春期中) 下列行为中符合安全要求的是()A . 装运乙醇的包装箱上应贴上易燃液体的危险品标志图标B . 用点燃的火柴在液化气钢瓶口检验是否漏气C . 实验时,将水倒入浓硫酸中配制稀硫酸D . 进入煤矿井时,用火把照明3. (2分) (2017高一上·龙泉驿开学考) 下列装置能达到对应实验目的的是()A . 图1.比较 MnO2和 Fe2O3的催化效果B . 图2制取并收集CO2气体C . 证明 CO2和 NaOH已发生反应D . 形成蓝色喷泉4. (2分)引燃密闭容器中的己烷和氧气的混合气体,使其发生不完全燃烧.在120℃时测得反应前后气体的压强分别为1.8×105帕和2.6×105帕,根据上述实验数据,确定己烷与氧气反应的化学方程式是()A . C6H14+9O2CO+5CO2+7H2OB . C6H14+8O23CO+3CO2+7H2OC . C6H14+9O25CO+CO2+7H2OD . C6H14+15O28CO+4CO2+14H2O5. (2分) (2017高一上·北京期中) CO2的相对分子质量为44,则一个CO2分子的质量为 (设NA为阿伏加德罗常数的值)()A . gB . gC . 44NA gD . g6. (2分)下列厨房中的活动不涉及化学变化的是()A . 菜刀切咸肉后未处理而生锈B . 用食醋除去水壶中的水垢C . 用葡萄自酿葡萄酒D . 将黄瓜切成片7. (2分)(2018·太原模拟) 南海是一个巨大的资源宝库,开发利用这些资源是科学研究的重要课题。

黑龙江省大庆实验中学2020-2021学年高二下学期期中理科数学试题

黑龙江省大庆实验中学2020-2021学年高二下学期期中理科数学试题

黑龙江省大庆实验中学2020-2021学年高二下学期期中理科数学试题学校:___________姓名:___________班级:___________考号:___________一、单选题1.已知复数31z i =-+,则在复平面内z 对应的点位于( ) A .第一象限B .第二象限C .第三象限D .第四象限2.命题“1x x e x R ∀∈+,≥”的否定是 A .1x x e x R ∀∈<+, B .0001xx e x R ∃∈+,≥ C .1x x e x R ∀∉<+,D .0001x x e x R ∃∈<+,3.设集合2{|4},{|0}A x x B x x ≤==<,则()RA B ⋃=( )A .{|2}x x ≥B .{|2}x x >C .{|2x x <-或02}x ≤<D .{|2x x ≤-或02}x <≤4.已知双曲线22221(00)y x a b a b-=>>,( )A .12y x =±B .y x =±C .y =D .2y x =±5.复数4312ii--的共轭复数....的虚部..为( ) A .1B .1-C .iD .i -6.在极坐标系中,点3,6π⎛⎫⎪⎝⎭到直线)sin 2ρθθ+=的距离为( )A .2B .1C .34D 17.我校实验二部数学学习兴趣小组为研究某作物种子的发芽率y 和温度x (单位:C ︒)的关系,由实验数据得到右面的散点图. 由此散点图,最适宜作为发芽率y 和温度x 的回归方程类型的是 ( )A .y a bx =+B .ln y a b x =+C .e x y a b =+D .2y a bx =+8.已知甲盒子有6个不同的小球,编号分别为1,2,3,4,5,6,从甲盒子中取出一个球,记随机变量X 是取出球的编号,数学期望为()E X ,乙盒子有5个不同的小球,编号分别为1,2,3,4,5,从乙盒子中取出一个球,记随机变量Y 是取出球的编号,数学期望为()E Y ,则( ) A .(3)(3)P X P Y =>=且()()E X E Y > B .(3)(3)P X P Y =>=且()()E X E Y < C .(3)(3)P X P Y =<=且()()E X E Y >D .(3)(3)P X P Y =<=且()()E X E Y <9.某工厂为了对新研发的一种产品进行合理定价,将该产品按事先拟定的价格进行试销,得到如下数据:由表中数据,求得线性回归方程为ˆˆ106y bx=+若在这些样本点中任取一点,则它在回归直线右上方的概率为( ) A .16B .13C .12D .2310.()6111x x ⎛⎫++ ⎪⎝⎭的展开式中x 的系数为( ) A .6B .15C .18D .2111.下列五个命题①在某项测量中,测量结果ξ 服从正态分布2(2,)(0)N σσ> ,若ξ在(0,2)内取值的概率为0.4,则ξ在(0,+∞)内取值的概率为0.8;②集合{}2230A x x x =∈+-≤Z ,{}02B x x =≤≤,则AB 的真子集个数为3;③命题“若2430x x -+=,则3x =”的逆否命题为“若3x ≠,则2430x x -+≠”;④若2nx⎛ ⎝的展开式中各项的二项式系数之和为32,则此展开式中2x 项的系数为80;⑤在10道题中有7道理科题和3道文科题,如果不放回地依次抽取2道题,在第1次抽到理科题的条件下,第2次抽到理科题的概率为23. 其中正确的个数为( ) A .2B .3C .4D .512.大庆体育场由于形似国家体育场,被大庆人称为“大庆鸟巢”,国家体育场(鸟巢)是第24届冬季奥林匹克运动会开、闭幕式的场馆.第24届冬季奥林匹克运动会,将在2022年2月4日在中华人民共和国北京市和张家口市联合举行.这是中国历史上第一次举办冬季奥运会,北京成为奥运史上第一个举办夏季奥林匹克运动会和冬季奥林匹克运动会的城市.同时中国也成为第一个实现奥运“全满贯”(先后举办奥运会、残奥会、青奥会、冬奥会、冬残奥会)国家.国家体育场“鸟巢”的钢结构鸟瞰图如图所示,内外两圈的钢骨架是离心率相同的椭圆,若由外层椭圆长轴一端点A 和短轴一端点B 分别向内层椭圆引切线AC ,BD (如图),且两切线斜率之积等于45-,则椭圆的离心率为( )A .15B .25C D二、填空题13.设随机变量ξ服从二项分布16,2B ⎛⎫⎪⎝⎭,则()2P ξ≤等于__________ 14.设命题:p 关于x 的一元二次方程()2220x a x a +++-=的一根大于零,另一根小于零; 命题:q x R ∀∈,2280x x a -+>; 若p q ∨为真命题,p q ∧为假命题,则实数a 的取值范围是___________.15.大庆实验中学文学社中甲、乙、丙、丁、戊、己这六名即将毕业的高三成员从左到右站成一排拍照留念,其中甲不站在队伍的两端,乙、丙两人不相邻,丁必须站在戊的左面(丁、戊两人可以相邻,也可以不相邻),则满足条件的不同站队方式的站法数为__________.(用数字作答) 16.已知关于x 的方程()1ln 20x xea x x a --+-=在(]0,1上有两个不相等的实根,则实数a 的取值范围是________三、解答题17.在平面直角坐标系xOy 中,曲线C的参数方程为2cos x y αα=⎧⎪⎨=⎪⎩(α是参数),在以原点为极点,x 轴正半轴为极轴的极坐标系中,直线l的极坐标方程为sin 4πρθ⎛⎫-= ⎪⎝⎭(1)求曲线C 和直线l 的普通方程;(2)设点()0,2P ,直线l 与曲线C 交于,A B 两点,求11PA PB+的值. 18.作为世界最大棉花消费国、第二大棉花生产国,我国2020-2021年度棉花产量约595万吨,总需求量约780万吨,年度缺口约185万吨.其中,新疆棉产量520万吨,占国内产量比重约87%,占国内消费比重约67%.新疆地区的棉花是世界上最好的棉花之一,新疆长绒棉,世界顶级,做衣被,暖和、透气、舒适,长年供不应求.评价棉花质量的重要指标之一就是棉花的纤维长度,新疆农科所在土壤环境不同的A 、B 两块实验地分别种植某品种的棉花,为了评价该品种的棉花质量,在棉花成熟后,分别从A 、B 两地的棉花中各随机抽取40根棉花纤维进行统计,结果如下表:(记纤维长度不低于300mm 的为“长纤维”,其余为“短纤维”).(1)由以上统计数据,填写下面22⨯列联表,并判断能否在犯错误概率不超过0.01的前提下认为“纤维长度与土壤环境有关系”(2K 的观测值精确到0.001) .附:(1)22()()()()()n ad bc K a b c d a c b d -=++++ (2)临界值表;(2)现从抽取的80根棉花纤维中“短纤维”里任意抽取2根做进一步研究,记B地“短纤维”的根数为ξ,求ξ的分布列和数学期望.(3)根据上述B 地关于“长纤维”与“短纤维”的调查,将B 地“长纤维”的频率视为概率,现从B 地棉花(大量的棉花)中任意抽取3根棉花,记抽取的“长纤维”的根数为X ,求X 的分布列及数学期望.19.如图,四棱锥P ABCD -中,底面ABCD 为平行四边形,90ADB ∠=︒,2AD =,DB = PD ⊥底面ABCD .(1)证明:BD PA ⊥;(2)若点E 为AD 的中点,3PD =,求二面角E PB D --的余弦值.20.在平面直角坐标系xOy 中,曲线1:C 2212x y +=,曲线2:C 4y =,以直角坐标系的原点作为极点,x 轴的正半轴作为极轴,并在两种坐标系中取相同的长度单位,射线:l θα=02πα⎛⎫<< ⎪⎝⎭与曲线1C 、曲线2C 分别交于点A 、B ,将射线l 绕极点逆时针旋转2π后得到射线l ',射线l '与曲线1C 、曲线2C 分别交于点C 、D . (1)求曲线1C 与曲线2C 的极坐标方程; (2)求2222OB OD OAOC+的最小值.21.已知12,F F 为椭圆:M ()222210x y a b a b +=>>椭圆上任意一点到12,F F 的距离之和为4. (1)求椭圆M 的标准方程;(2)过1F 的直线12,l l 分别交椭圆M 于,A C 和,B D ,且12l l ⊥,试求四边形ABCD 的面积S 的取值范围.22.已知函数()1xf x e x =--,()2xg x e x =-.(1)(ⅰ)证明: ()0f x ≥; (ⅱ)证明:()0g x >.(2)当0x ≥时,()()sin 1cos 1f x x x x ax +++≥+恒成立,求实数a 的取值范围.参考答案1.C 【分析】由复数的乘方把复数化为代数形式,可得其对应点的坐标,得出结论. 【详解】311z i i =-+=--,对应点为(1,1)--,在第三象限.故选:C . 2.D 【分析】利用全称命题的否定是特称命题,写出结果即可 【详解】因为全称命题的否定是特称命题,所以命题“x R ∀∈,1x e x ≥+”的否定是0x R ∃∈,001x e x <+故选D 【点睛】本题主要考查了全称命题的否定是特称命题,属于基础题. 3.B 【分析】先解一元二次不等式化简集合A ,再求并集和补集即可. 【详解】集合()(){}}{2{|4}22022A x x x x x x x =≤=+-≤=-≤≤,{|0}B x x =<,故}{2A B x x ⋃=≤,则()RA B ⋃={|2}x x >.故选:B. 4.C 【分析】直接利用222,c e c a b a ==+进行齐次转化得到ba=,即得结果. 【详解】双曲线中,222c e c a b a ===+,所以b a =====故该双曲线的渐近线方程为y =. 故选:C. 5.B 【分析】利用复数代数形式的乘除运算化简,再由共轭复数的概念求得z ,则答案可求. 【详解】 ∵()()()()431+243105=212121+25i i i i z i i i i --+===+--, ∴2z i =-,故共轭复数的虚部为1-, 故选:B 6.A 【分析】将点的极坐标和直线的极坐标方程化为直角坐标和直角坐标方程,再根据点到直线的距离求解即可. 【详解】将点3,6π⎛⎫⎪⎝⎭化为直角坐标得:3,22⎛⎫ ⎪ ⎪⎝⎭,直线)sin 2ρθθ+=20y +-=,所以点3,6π⎛⎫⎪⎝⎭到直线)sin 2ρθθ+=的距离为2d ==.故选:A 【点睛】 关键点点睛:本题解题的关键在于将极坐标与极坐标方程化为直角坐标与直角坐标方程,进而计算距离突7.B 【分析】先利用散点图判断增长状态,再逐个分析选项是否合适即可. 【详解】由散点图可见,数据分布成递增趋势,但是呈现上凸效果,即增加缓慢. A 中,y a bx =+是直线型,均匀增长,不符合要求; B 中,ln y a b x =+是对数型,增长缓慢,符合要求;C 中,e x y a b =+是指数型,爆炸式增长,增长快,不符合要求;D 中,2y a bx =+是二次函数型,图象呈现下凸,增长也较快,不符合要求. 故对数型最适宜该回归模型. 故选:B. 8.C 【分析】求出(3),(3)P X P Y ==,(),()E X E Y ,即得解. 【详解】 由题1(3)6P X ==,1(3)5P Y ==, 1111117()1234566666662E X =⨯+⨯+⨯+⨯+⨯+⨯=,11111()12345355555E Y =⨯+⨯+⨯+⨯+⨯=.故选:C 【点睛】本题主要考查概率的计算和随机变量的期望的计算,意在考查学生对这些知识的理解掌握水平. 9.C 【详解】 略 10.D略 11.C 【分析】根据正态分布的对称性判断①,求出交集后判断②,根据逆否命题的定义判断③,由二项式系数和求得n ,现由二项式定理判断④,利用古典概型概率公式计算判断⑤. 【详解】ξ2(2,)(0)N σσ>,而()020.4P ξ<<=,所以(0)(02)(2)0.40.50.9P P P ξξξ>=<<+>=+=,①错;{}{}{}2230313,2,1,0,1A x x x x x =∈+-≤=∈-≤≤=---Z Z ,{0,1}A B =,真子集个数为3,②正确;命题“若2430x x -+=,则3x =”的逆否命题为“若3x ≠,则2430x x -+≠”,③正确;若2nx ⎛ ⎝的展开式中各项的二项式系数之和为32,则232n=,5n =,则展开式通项公式为35552155(2)((1)2r rrr r r rr T C x C x ---+==-,令3522r -=,2r,所以2x 的系数为2325(1)280C -⨯⨯=,④正确;在10道题中有7道理科题和3道文科题,如果不放回地依次抽取2道题,在第1次抽到理科题的条件下,剩下6道理科题,3道文科题,第2次抽到理科题的概率为6293=,⑤正确. 正确命题有4个. 故选:C . 【点睛】本题考查命题的真假判断,难度较大,必须掌握多种知识点,才能正确求解.如正态分布,集合的交集运算与子集的定义,命题与逆否命题,二项式定理,古典概型.注意空集是非空集合的真子集,本题第⑤个命题也可用条件概率公式计算,如设事件A 表示第一次抽到理科试题,B 表示第二次抽到理科试题,则7()10P A =,272107()15C P AB C ==,则()2(|)()3P AB P B A P A ==. 12.D 【详解】 略 13.1132【分析】将(2) P ξ转化为求(0)(1)(2)P P P ξξξ=+=+=,即可得到答案; 【详解】(2)(0)(1) (2)P P P P ξξξξ==+=+=06152401266611111116151122222264646432C C C ⎛⎫⎛⎫⎛⎫⎛⎫⎛⎫⎛⎫=⋅+⋅+⋅=++= ⎪ ⎪ ⎪ ⎪ ⎪ ⎪⎝⎭⎝⎭⎝⎭⎝⎭⎝⎭⎝⎭, 故答案为:1132. 14.[)()4,24,-+∞【分析】先按命题p 和q 是真命题时求解参数范围,按照假命题时取补集,再结合题意知命题p 和q 一真一假,列不等式组,解得答案即可. 【详解】若命题p 是真命题,则一元二次方程()2220x a x a +++-=中,判别式()()222a a ∆=+-4->0,且两根之积20a -<,解得2a <;若命题q 是真命题,则一元二次不等式对应的方程2280x x a -+=中,判别式∆<0,即26440a -<,即216a >.p q ∨为真命题,p q ∧为假命题,则命题p 和q 一真一假.当p 真,q 假时,有2216a a <⎧⎨≤⎩,解得42a -≤<; 当p 假,q 真时,有2216a a ≥⎧⎨>⎩,解得4a >.综上,实数a 的取值范围是[)()4,24,-+∞.故答案为:[)()4,24,-+∞.【点睛】 方法点睛:二次函数()20f x ax bx c =++>在R 上恒成立,等价于00a >⎧⎨∆<⎩;二次函数()20f x ax bx c =++<在R 上恒成立,等价于00a <⎧⎨∆<⎩; 二次函数()20f x ax bx c =++≥在R 上恒成立,等价于00a >⎧⎨∆≤⎩;二次函数()20f x ax bx c =++≤在R 上恒成立,等价于0a <⎧⎨∆≤⎩.15.168 【分析】利用正难则反的策略,先弱化甲不站在队伍的两端,先排甲、丁、戊、己,然后不相邻插空,再减去甲站在队伍的两端的情况,即可得到结果. 【详解】先排甲、丁、戊、己,且丁必须站在戊的左面,共4422A A 种排法,然后再排乙、丙,且两人不相邻,共25A 种排法,此时共424522240A A A ⋅=种排法,当甲站在队伍的两端时,共3123242272A C A A ⋅⋅=种排法,∴满足条件的不同站队方式的站法数为24072168-=种排法 故答案为:168 【点睛】方法点睛:求解排列、组合问题常用的解题方法:(1)元素相邻的排列问题——“捆邦法”;(2)元素相间的排列问题——“插空法”;(3)元素有顺序限制的排列问题——“除序法”;(4)带有“含”与“不含”“至多”“至少”的排列组合问题——“间接法”; (5) “在”与“不在”问题——“分类法”. 16.211,3e ⎛⎤⎥⎝⎦ 【分析】先利用指、对数性质整理方程为()ln 1ln 20x x ea x x a +--+-=,令ln 1t x x =+-,(]0,1x ∈,即得3te a t =+在()(],33,0t ∈-∞--有两个不相等的实根,再转化为y a =和()3te g t t =+,()(],33,0t ∈-∞--有两个不同的交点,利用导数研究函数图象,并结合图象得到结果即可. 【详解】解: 由ln x x e =,则方程()1ln 20x xea x x a --+-=,即()ln 1ln 20x x e a x x a +--+-=,令ln 1t x x =+-,(]0,1x ∈,则由ln ,1y x y x ==-单调性可知,函数ln 1t x x =+-是递增的,故(]0,1x ∈时,值域为(],0t ∈-∞.而()ln 1ln 20x x ea x x a +--+-=转化为30t e at a --=,当3t =-时,方程为0te =,不成立,故3t ≠-,即转化为3te a t =+在()(],33,0t ∈-∞--有两个不相等的实根,即y a =和()3te y g t t ==+,()(],33,0t ∈-∞--有两个不同的交点.()()()223t e x g t t +'=+,当(),3t ∈-∞-和(]3,2t ∈--时,()0g t '<,即()g t 在(),3t ∈-∞-上递减,在(]3,2t ∈--上递减;当(]2,0t ∈-时,()0g t '>,()g t 递增.另外,3t <-时,()03te g t t =<+;3t >-时,()0g t >;()()2112,03g g e -==.结合函数()3te y g t t ==+,()(],33,0t ∈-∞--图象可知,当211,3a e ⎛⎤∈ ⎥⎝⎦时,y a =和()3te g t t =+,()(],33,0t ∈-∞--的图象有两个不同的交点.故答案为:211,3e ⎛⎤⎥⎝⎦. 【点睛】方法点睛:已知函数有零点(方程有根)或已知零点个数(方程根的个数)求参数值(取值范围)常用的方法:(1)直接法:直接求解方程得到方程的根,再通过解不等式确定参数范围; (2)分离参数法:先将参数分离,转化成求函数的值域问题加以解决;(3)数形结合法:先对解析式变形,进而构造两个函数,然后在同一平面直角坐标系中画出函数的图象,利用数形结合的方法求解.17.(1)C :22143x y +=,l :2y x =+;(2)【分析】(1)消去参数α得普通方程,利用公式cos sin x y ρθρθ=⎧⎨=⎩可化极坐标方程为直角坐标方程;(2)把直线方程化为标准参数方程,代入曲线C 的直角坐标方程,利用参数几何意义计算. 【详解】(1)由2cos x y αα=⎧⎪⎨=⎪⎩得22143x y +=,即为C 的普通方程,由sin 4πρθ⎛⎫-= ⎪⎝⎭得(sin cos cos sin )44ππρθθ-=sin cos 2ρθρθ-=, 2y x -=,直线l 的直角坐标方程为20x y -+=;(2)(0,2)P 在直线l上,可得其参数方程为2x y ⎧=⎪⎪⎨⎪=⎪⎩(t 为参数),把2x y ⎧=⎪⎪⎨⎪=⎪⎩代入22143x y +=得,27402t ++=,所以127t t +=-,1287t t =,12,t t均为负.12121212121111787t t t t PA PB t t t t t t +++=+====【点睛】方法点睛:本题考查参数方程与普通方程的互化,极坐标方程与直角坐标方程的互化,直线与椭圆相交的线段长问题,解题方法是参数法,利用直线的标准参数方程中参数t 的几何意义求解.求出直线的标准参数方程,代入曲线的直角坐标方程,应用韦达定理计算. 18.(1)表格见解析,可以在犯错误的概率不超过0.01的前提下认为“纤维长度与土壤环境有关系”;(2)分布列见解析,12;(3)分布列见解析,218. 【分析】(1)根据题意纤维长度不低于300mm 的为“长纤维”,其余为“短纤维”,统计填表即可,再计算观测值2K ,与附表对照,判断即得结果;(2)依题意随机变量服从超几何分布,先写随机变量取值,再利用组合计算对应概率,即得分布列和数学期望;(3)依题意随机变量服从二项分布,再根据二项分布的概率分布公式计算概率,得到分布列和数学期望即可. 【详解】解:(1)根据已知数据得到如下22⨯列联表:根据22⨯列联表中的数据,可得2280(2551535) 6.66740402060K ⨯⨯-⨯=≈⨯⨯⨯,因为6.667 6.635>,所以可以在犯错误的概率不超过0.01的前提下认为“纤维长度与土壤环境有关系”; (2)由题意可知,抽取的80根棉花纤维中“短纤维”有20根,A 地15根,B 地5根,从中任意抽取2根做进一步研究,则B地“短纤维”的根数ξ的可能取值为:0,1,2,21522021(0)38C P C ξ===,1115522015(1)38C C P C ξ===,252201(2)19C P C ξ===,故ξ的分布列为:所以 211511()0123838192E ξ=⨯+⨯+⨯=; (3)由表中数据可知,抽到的棉花为“长纤维”的概率为357408= , 依题意,将B 地“长纤维”的频率视为概率,从B 地棉花(大量的棉花)中任意抽取3根棉花,则抽取的“长纤维”的根数7~3,8X B ⎛⎫ ⎪⎝⎭,所以30371(0)18512P X C ⎛⎫==-= ⎪⎝⎭,2137721(1)188512P X C ⎛⎫==-= ⎪⎝⎭, 22377147(2)188512P X C ⎛⎫⎛⎫==-= ⎪⎪⎝⎭⎝⎭,3337343(3)8512P X C ⎛⎫=== ⎪⎝⎭. 故X 的分布列为故X 的期望为()721388E X =⨯=. 【点睛】 思路点睛:求离散型随机变量的分布列及期望的一般步骤: (1)根据题中条件确定随机变量的可能取值;(2)求出随机变量所有可能取值对应的概率,即可得出分布列;(3)根据期望的概念,结合分布列,即可得出期望(在计算时,要注意随机变量是否服从特殊的分布,如超几何分布或二项分布等,可结合其对应的概率计算公式及期望计算公式,简化计算).19.(1)证明见解析;(2【分析】(1)先证得PD BD ⊥,得BD ⊥平面PAD 则可得证线线垂直;(2)以D 为坐标原点,,,DA DB DP 为,,x y z 轴建立如图所示的空间直角坐标系D xyz -,由空间向量法求二面角. 【详解】证明: 因为PD ⊥底面ABCD ,BD ⊂平面ABCD ,所以PD BD ⊥, 又因为90ADB ∠=,BD AD ⊥. PD AD D ⋂=,,PD AD ⊂平面PAD , 所以BD ⊥平面PAD . 又PA ⊂平面PAD ,从而BD PA ⊥(2)因为PD ⊥底面ABCD ,所以PD AD ⊥,又BD AD ⊥,PD BD ⊥, 所以,,DA DB DP 两两垂直,如图,以D 为坐标原点,DA 的方向为x 轴的正方向,建立空间直角坐标系D xyz -,则(2,0,0)A ,B ,()0,0,3P ,()1,0,0E .(2,0,0)DA =, (1EB =-,(1,0,3)EP =-,设(,,)m x y z =为平面EPB 的法向量,则0,0,m EB m EP ⎧⋅=⎨⋅=⎩即0,30,x x z ⎧-+=⎪⎨-+=⎪⎩,可取(6,3,2)m =,又因为AD PD ⊥,AD BD ⊥,PD BD D ⋂=,,PD BD ⊂平面PBD ,所以AD ⊥平面PBD ,所以(2,0,0)DA =为平面DPB 的法向量,则cos ,243DA m DA m DA m⋅===⨯⋅故二面角E PB D --的余弦值为6 【点睛】方法点睛:本题考查证明线线垂直,求二面角.求二面角的方法:(1)几何法(定义法):根据定义作出二面角的平面角并证明,然后解三角形得出结论; (2)空间向量法:建立空间直角坐标系,写出各点为坐标,求出二面角两个面的法向量,由两个平面法向量的夹角得二面角(它们相等或互补).20.(1)222=1+sin ρθ,sin =ρθ4;(2)48.【详解】 略21.(1)2214x y +=;(2)32,225⎡⎤⎢⎥⎣⎦. 【分析】(1)由椭圆的定义及离心率的意义求出a ,b 即可得解;(2)按直线l 1的斜率是否存在及是否为0的三种情况讨论,分别求出AC ,BD 长,再建立起S 的函数关系,探讨其值域即可得解. 【详解】(1)由椭圆定义知2a =4,即a =2,又离心率c e a ==得半焦距c =2221b a c =-=, 所以椭圆M 的标准方程为:2214x y +=;(2)由(1)知点1(F ,①当直线1l 的斜率为0时,直线1l 的方程为0y =,则24AC a ==,直线2l的方程为x =则2l 与椭圆M的二交点坐标为1()2,1()2-,此时1BD =,可得1141222S AC BD ==⨯⨯=; ②当直线1l 的斜率不存在时,直线1l的方程为x =1l 与椭圆M的二交点坐标为1()2,1()2-,此时1AC =, 直线2l 的方程为0y =,则24BD a ==,可得1114222S AC BD ==⨯⨯=; ③当直线1l 的斜率存在且不为0时,设直线1l 的斜率为()0k k ≠,则直线(1:l y k x =+,由22(14y k x x y ⎧=⎪⎨+=⎪⎩得()2222141240k x x k +++-=, 216160k ∆=+>,设()()1122,,,A x y B x y,则21212212414k x x x x k-+==+,所以12AC x =-=()224114k k +==+, 同理可得()22414k BD k +=+,所以()()()()22422424222228182111818224241744174414417k k k k S AC BD k k k k k k k k+++=⋅===-=-++++++++.由于22448k k +≥(当1k =±时取等号),22441725k k++≥,22110425417k k<≤++, 2218180425417k k <≤++,22321822425417k k≤-<++,所以32225S ≤<, 综合①②③可知,四边形ABCD 面积的取值范围是32,225⎡⎤⎢⎥⎣⎦. 【点睛】结论点睛:直线l :y =kx +b 上两点A (x 1,y 1),B (x 2,y 2)间的距离12||||AB x x =-; 直线l :x =my +t 上两点A (x 1,y 1),B (x 2,y 2)间的距离12||||AB y y =-. 22.(1)(ⅰ)证明见解析;(ⅱ)证明见解析;(2)(],1-∞. 【分析】(1)通过研究导函数()f x '和()g x '的正负情况判断()f x 和()g x 的单调性,进而得到最值,即证结论;(2)先代入化简为0x ≥时,sin cos 20x e x x x ax ++--≥恒成立,构造函数()()sin cos 20x F x e x x x ax x =++--≥,通过两次求导判断其导函数的的单调性,再对a 进行分类讨论,结合(1)中结论判断()0F x ≥能否成立,即得结果. 【详解】解:(1)(ⅰ)证明:由()1xf x e x =--可知()1xf x e '=-.当(),0x ∈-∞时,()0f x '<,函数()f x 单调递减,当()0,x ∈+∞时,()0f x '>,函数()f x 单调递增,当0x =时,函数()f x 有最小值()0f ,又()00f =,故()0f x ≥; (ⅱ)证明:由()2x g x e x =-可知,()2xg x e '=-. 当(),ln 2x ∈-∞时,()0g x '<,函数()g x 单调递减,当()ln 2,x ∈+∞时,()0g x '>,函数()g x 单调递增,当ln 2x =时,函数()g x 有最小值()ln 2g ,又()ln 222ln 22ln 02e g =-=>,故()0g x >. (2)当0x ≥时,()()sin 1cos 1f x x x x ax +++≥+恒成立,而()1x f x e x =--,故不等式等价于当0x ≥时,sin cos 20x e x x x ax ++--≥恒成立.设函数()()sin cos 20xF x e x x x ax x =++--≥. 则()cos x F x e x x a '=+-,设()()cos 0xh x e x x a x =+-≥, 则()sin cos xh x e x x x '=-+. 当0x ≥时,cos 1x ≥-,sin 1x -≥-,sin x x x -≥-,结合(1)(ⅰ)问结论()0f x ≥知,()sin cos 10x x h x e x x x e x '=-+≥--≥,故函数()h x 在[)0,+∞上单调递增.若1a ≤,则当0x ≥时,()()010h x h a ≥=-≥,()0F x '≥,函数()F x 在在[)0,+∞上单调递增,又()00F =,故()0F x ≥,满足题意;若1a >,因为cos 1a ≥-,cos a a a ≥-,结合(1)(ⅱ)问结论()0g x >可知,()cos 20a a ah a e a a a e a a e a =+-≥--=->, 又()010h a =-<,函数()h x 在[)0,+∞上单调递增,故存在()00,x a ∈,使得()00h x =,当()00,x x ∈时,()0h x <,()0F x '<,函数()F x 在()00,x 上单调递减,此时()()0F x F <,又()00F =,即当()00,x x ∈时,()0F x <,不符题意.故实数a 的取值范围是(],1-∞.【点睛】关键点点睛:第一问中证明不等式的关键在于利用函数导数研究最值,第二问的解题关键在于分类讨论后巧妙利用(1)中结论进行判断,突破难点.。

2020-2021学年黑龙江省大庆实验中学高二下学期期中数学复习卷(2)(含解析)

2020-2021学年黑龙江省大庆实验中学高二下学期期中数学复习卷(2)(含解析)

2020-2021学年黑龙江省大庆实验中学高二下学期期中数学复习卷(2)一、单选题(本大题共21小题,共60.0分)1.已知集合M={0,1,2,3,4},N={1,3,5},P=M∩N,则P的真子集有()A. 3个B. 4个C. 6个D. 8个2.已知i为虚数单位,复数z=2i(2−i)的实部为a,虚部为b,则log a b等于()A. 0B. 1C. 2D. 33.θ=π4(ρ≥0)表示的图形是()A. 一条直线B. 一条射线C. 一条线段D. 圆4.集合,,给出下列四个图形,其中能表示以为定义域,为值域的函数关系的是().A.B.C.D.A. AB. BC. CD. D5.如图,若图中直线 1, 2, 3的斜率分别为k1,k2,k3,则A. k1<k2<k3B. k3<k1<k2C. k3<k2<k1D. k1<k3<k26.命题“∀x∈[0,+∞),e x≥1+sinx”的否定是()A. ∀x∈[0,+∞),e x<1+sinxB. ∀x∉[0,+∞),e x≥1+sinxC. ∃x∈[0,+∞),e x<1+sinxD. ∃x∉[0,+∞),e x<1+sinx7.已知椭圆x2a2+y2b2=1(a>b>0)的离心率为2√55,以原点为圆心,以椭圆短半轴长为半径的圆与直线y=2x+1相切,则a=()A. 2B. √5C. √3D. 18.若f(x)在R上是奇函数,且有f(x+4)=f(x),当x∈(0,2)时,f(x)=2x2,则f(11)=()A. 242B. −242C. 2D. −29. 设命题p :lg(2x −1)≤0,命题q :x−(a+1)x−a≤0,若q 是p 的必要不充分条件,则实数a 的取值范围是( )A. [0,12]B. (0,12)C. [0,12)D. ⌀10. 在同一平面直角坐标系中,经过伸缩变换{x′=7xy′=4y后,曲线C 变为曲线x′2+8y′2=1,则曲线C 的方程为( )A. 49x 2+128y 2=1B. 49x 2+64y 2=1C. 49x 2+32y 2=1D. 249x 2+12y 2=111. 对于任意的两个实数对(a,b)和(c,d),规定(a,b)=(c,d)当且仅当a =c ,b =d ;运算“⊗”为:(a,b)⊗(c,d)=(ac −bd,bc +ad), 运算“⊕”为:(a,b)⊕(c,d)=(a +c,b +d),设p ,q ∈R ,若(1,2)⊗(p,q)=(5,0),则(1,2)⊕(p,q)=( )A. (0,−4)B. (4,0)C. (0,2)D. (2,0)12. 1.设椭圆(m >0,n >0)的右焦点与抛物线y 2=8x 的焦点相同,离心率为,则此椭圆的方程为( )A. B. C.D.13. 2.下列结论错误的是A. 若“p 且q ”与“﹁p 或q ”均为假命题,则p 真q 假.B. 若一个命题的逆命题为真,则它的否命题也一定为真;C. “x =1”是“x 2−3x +2=0”的充分不必要条件.D. “若am 2<bm 2,则a <b ”的逆命题为真.14. 3.是成立的A. 充分不必要条件B. 必要不充分条件C. 充要条件D. 既不充分也不必要条件15. 4.若椭圆的离心率,则m 值A. 3B. 3或C.D. 或16. 5.函数f(x)=ax 3−x在R上为减函数,则()A. a≤0B. a<1C. a<2D.17. 6.设,则方程不能表示的曲线为A. 椭圆B. 双曲线C. 抛物线D. 圆18.7.在三棱锥P−ABC中,PA⊥平面ABC,∠BAC=90°,D,E,F分别是棱AB,BC,CP的中点,AB=AC=1,PA=2,则直线PA与平面DEF所成角的正弦值为()A. B. C. D.19.8.已知点在曲线上,为曲线在点处的切线的倾斜角,则的取值范围是A. B. C. D.20.9.过抛物线的焦点的直线交抛物线于两点,点是原点,若;则的面积为()A. B. C. D.21.10.直线L经过双曲(a>0,b>0)右焦点F与其一条渐近线垂直且垂足为A,与另一条渐近线交于B点,=,则双曲线的离心率为()A. B. C. D. 2二、单空题(本大题共4小题,共20.0分)22.i是虚数单位,则|i1+i|的值为______.23.在平面上取定一点O,从O出发引一条射线Ox,再取定一个长度单位及计算角度的正方向(取逆时针方向为正),就称建立了一个极坐标系,这样,平面上任一点P的位置可用有序数对(ρ,θ)确定,其中ρ表示线段OP的长度,θ表示从Ox到OP的角度.在极坐标系下,给出下列命题:(1)平面上的点A(2,−π6)与B(2,2kπ+11π6)(k∈Z)重合;(2)方程θ=π3和方程ρsinθ=2分别都表示一条直线;(3)动点A在曲线ρ(cos2θ2−12)=2上,则点A与点O的最短距离为2;(4)已知两点A(4,2π3),B(4√33,π6),动点C在曲线ρ=8上,则△ABC面积的最大值为40√33.其中正确命题的序号为______ (填上所有正确命题的序号).24.观察如图,则第______行的各数之和等于20172.12 3 43 4 5 6 74 5 6 7 8 9 10…25.过抛物线y2=4x的焦点作直线交抛物线于A(x1,y1)、B(x2,y2)两点,若x1+x2=10,则弦AB的长度为______ .三、解答题(本大题共6小题,共70.0分)26.已知命题p:关于x的方程x2+2x+a=0有实数解,命题q:关于x的不等式x2+ax+a>0的解集为R,若(¬p)∧q是真命题,求实数a的取值范围.27.在平面直角坐标系xOy中,以坐标原点为极点,x轴的正半轴为极轴建立极坐标系,已知在极坐标系中,A(3√3,π2),B(3,π3),圆C的方程为ρ=2cosθ.(1)求在平面直角坐标系xOy中圆C的标准方程;(2)已知P为圆C上的任意一点,求△ABP面积的最大值.28.已知函数f(x)=x2+2ax,x∈[−5,5].(1)若y=f(x)−2x是偶函数,求f(x)的最大值和最小值;(2)如果f(x)在[−5,5]上是单调函数,求实数a的取值范围。

黑龙江省大庆市大庆实验中学2020-2021学年高二英语下学期开学考试试题

黑龙江省大庆市大庆实验中学2020-2021学年高二英语下学期开学考试试题

黑龙江省大庆市大庆实验中学2020-2021学年高二英语下学期开学考试试题年级:姓名:黑龙江省大庆市大庆实验中学2020-2021学年高二英语下学期开学考试试题(含解析)第一部分听力 (共两节,满分 20 分)第一节听下面 5 段对话。

每段对话后有一个小题,从题中所给的 A、B、C 三个选项中选出最佳选项,并标在试卷的相应位置。

听完每段对话后,你都有 10 秒钟的时间来回答有关小题和阅读下一小题。

每段对话仅读一遍。

1. What did the man buy for his father?A. A hat.B. A card.C. A shirt.2. How will Tom know if the school is canceled?A. By asking his mother.B. By watching the snow.C. By checking the TV news.3. Where was the man born?A. In America.B. In England.C. In Canada.4. What does the man mean?A. Anna may not have time.B. Anna is at her brother’s house.C. Anna should invite him to dinner.5. What does the man think of the music festival this year?A. It’s too far away.B. It’s too expensive.C. It’s too crowded.第二节听下面 5 段对话或独白。

每段对话或独白后有几个小题,从题中所给的 A、B、C 三个选项中选出最佳选项。

听每段对话或独白前,你将有时间阅读各个小题,每小题 5 秒钟;听完后,各小题将给出 5 秒钟的作答时间。

黑龙江省大庆实验中学2020-2021学年高二下学期开学考试物理试题含答案解析

黑龙江省大庆实验中学2020-2021学年高二下学期开学考试物理试题含答案解析

【全国百强校】黑龙江省大庆实验中学【最新】高二下学期开学考试物理试题学校:___________姓名:___________班级:___________考号:___________一、单选题1.甲、乙两车在一平直公路上从同一地点沿同一方向沿直线运动,它们的v t 图像如图所示.下列判断正确的是()A.乙车启动时的加速度大小为21m/sB.乙车启动时与甲车相距100mC.乙车启动20s后乙车正好超过甲车D.运动过程中,乙车落后甲车的最大距离为75m2.如图所示,质量为4kg的物体A静止在竖直的轻弹簧上面。

质量为1kg的物体B用细线悬挂起来,A、B紧挨在一起但A、B之间无压力。

某时刻将细线剪断,则细线剪断瞬间,B对A的压力大小为(g取l0m/s2)的()A.0 B.50N C.10N D.8N3.【最新】11月19日,我国在西昌卫星发射中心将两颗北斗全球导航卫星(即北斗三号卫星)发射升空,标志着我国北斗三号基本系统部署完成.此次发射的北斗三号系统第18颗和第19颗卫星,属于中圆地球轨道(介于近地轨道和同步静止轨道之间)卫星.当卫星在轨正常运行时,下列说法正确的是A .第18颗卫星的加速度大于地球表面的重力加速度B .第18颗卫星的运行速度介于第一宇宙速度和第二宇宙速度之间C .第19颗卫星的周期小于静止轨道卫星的周期D .第19颗卫星受到地球的万有引力小于同质量静止轨道卫星受到地球的万有引力 4.如图所示,一段均匀带电的半圆形细线在其圆心O 处产生的场强为E ,现把细线分成等长的AB 、BC 、CD 三段圆弧,请利用学过的方法(如对称性,叠加思想)分析,圆弧BC 在圆心O 点产生场强的大小是A .EB .2EC .3ED .4E 5.一圆筒处于磁感应强度为B 的匀强磁场中,磁场方向与筒的轴平行,筒的横截面如图所示. 图中直径MN 的两端分别开有小孔,筒绕其中心轴以角速度ω顺时针转动.在该截面内,一带电粒子从小孔M 射入筒内,射入时的速度方向与MN 成30°角.当筒转过90°时,该粒子恰好从小孔N 飞出圆筒,不计重力.若粒子在筒内未与筒壁发生碰撞,则带电粒子的比荷为( )A .B ωB .2B ωC .3B ωD .2Bω 6.如图所示,平行板电容器水平放置,上极板带正电且接地(大地电势为零),下极板带等量负电。

黑龙江省实验中学2020-2021学年高二物理下学期周测试题(5.21-23

黑龙江省实验中学2020-2021学年高二物理下学期周测试题(5.21-23

黑龙江省高二物理下学期周测试题(5.21-23,无答案)第I 卷(选择题)一、单选题(每题5分)1.下列有关原子、原子核的说法中正确的是( )A .天然放射现象说明原子核内部有电子B .卢瑟福用α粒子散射实验证明了原子核内存在中子C .结合能越大,原子核中的核子结合得越牢固,原子核越稳定D .在所有核反应中,都遵从“质量数守恒,电荷数守恒”的规律2.秦山核电站发电的能量来自于( )A .天然放射性元素衰变放出的能量B .原子核人工转变放出的能量C .重核裂变放出的能量D .化学反应放出的能量3.近代物理取得了非常辉煌的成就,下列关于近代物理的说法正确的是( )A .用同频率的光照射不同的的金属表面时均有光电子逸出,从金属表面逸出的光电子的最大初动能E k 越大,则这种金属的逸出功W 就越大B .137Cs 是核泄漏时对人体产生有害辐射的的重要污染物,其核反应方程式1371375556Cs Ba+X其中X 为电子C .一个氢原子处在n =4的能级,当它跃迁到较低能级时,最多可发出6种频率的光子D .每个核子只与邻近核子产生核力作用,比结合能越大的原子核越不稳定4.2017年11月17日,“中国核潜艇之父”----黄旭华获评全国道德模范,颁奖典礼上,习总书记为他“让座”的场景感人肺腑,下列有关核反应说法错误的是( )A .目前核潜艇是利用重核裂变提供动力B .重核裂变反应前后一定有质量亏损C .式中d=2D .铀核裂变后的新核比铀核的比结合能小5.日本福岛核事故是世界上最大的核事故之一,2019年2月13日日本宣布福岛核电站核残渣首次被“触及”,其中部分残留的放射性物质半衰期可长达1570万年,下列有关说法正确的是A .23892U 衰变成20682Pb 的核反应方程为2382064092822174U Pb He e -→++ B .23892U 的比结合能大于20682Pb 的比结合能C .天然放射现象中产生的α射线的速度与光速相当,穿透能力很强D .将由放射性元素组成的化合物进行高温分解,不会改变放射性元素的半衰期6.近代物理和技术的发展,极大地改变了人类的生产和生活方式,推动了人类文明与进步。

黑龙江省大庆实验中学2020┄2021学年高二下学期期中考试物理试题

黑龙江省大庆实验中学2020┄2021学年高二下学期期中考试物理试题

试卷总分110分,考试时间90分钟一、本题共15小题;每小题4分共计60分。

在每小题给出的四个选项中,有的小题只有一个选项正确,有的小题有多个选项正确。

全部选对的得4分,选不全的得2分,有选错或不答的得0分。

1.下列说法正确的是( )A.布朗运动是悬浮在液体中固体颗粒的分子无规则运动的反映B.布朗运动是作无规则运动的液体分子撞击微粒而引起的C.知道某物质的摩尔质量和密度可求出阿伏加德罗常数D.内能不同的物体,它们分子热运动的平均动能可能相同2.一滴油酸酒精溶液含质量为m 的纯油酸,滴在液面上扩散后形成的最大面积为S .已知纯油酸的摩尔质量为M、密度为ρ,阿伏加德罗常数为N A .下列表达式正确的有( )A .油酸分子的直径S M d ρ=ﻩB.油酸分子的直径Sm d ρ= C.一滴油酸所含的分子数A N M m n =D.一滴油酸所含的分子数A N m M n = 3.2013年6月20日我国女航天员王亚平在天宫一号上进行我国第一次太空授课,她不断用注射器向金属圆圈中的水膜里注入水,最后水膜变成了水球.分析形成水球的原因是( )ﻩA.水球在完全失重环境下不受任何力的作用B.水球所受的地球对它的引力只改变它的运动状态,对其形状无影响 C .对水球形状有影响的是水的表面张力,在其向各个方向大小相同的表面张力的作用下形成球体 ﻩD.以上说法均不正确4.下列说法中正确的是( )A .晶体一定具有各向异性,非晶体一定具有各向同性B.晶体的分子(或原子、离子)排列是有规则的C.液晶既像液体一样具有流动性,又跟某些晶体一样具有光学性质的各向异性D.单晶体和多晶体有固定的熔点,非晶体没有固定的熔点5.下列现象中,能说明液体存在表面张力的有( )A.水黾可以停在水面上B.叶面上的露珠呈球形C.滴入水中的红墨水很快散开D.悬浮在水中的花粉做无规则运动6.一定质量的理想气体,经等温压缩,气体的压强增大,用分子动理论的观点分析,这是因为( ) A.气体分子每次碰撞器壁的平均作用力增大B.单位时间内单位面积器壁上受到气体分子碰撞的次数增多C.气体分子的总数增加D.气体分子的密度增大7.下列有关气体分子动理论的说法中正确的是ﻩ()A.对大量分子整体统计,气体分子的运动是有规律的B.温度升高时每个气体分子的速率都将增大,因此气体分子的平均速率也将增大C.在一定温度下,某种气体的分子速率分布是确定的D.气体的压强只跟气体的温度有关,温度越高压强越大8.矩形线圈绕垂直磁场线的轴匀速转动,对于线圈中产生的交变电流()A.交变电流的周期等于线圈转动周期B.交变电流的频率等于线圈的转速C.线圈每次通过中性面,交变电流改变一次方向D.线圈每次通过中性面,交变电流达到最大值9.一交流电压为u=1002sin100πtV,由此表达式可知( )A.用电压表测该电压其示数为100 VB.该交流电压的周期为0.02 sC.将该电压加在100 Ω的电阻两端,电阻消耗的电功率为200 WD .t =1/400 s 时,该交流电压的瞬时值为100 V10.把一只电热器接到100 V 的直流电源上,在t 时间内产生的热量为Q ,若将它分别接到U 1=100s in ωt V 和U 2=50si n2ωt V 的交变电流电源上,仍要产生热量Q ,则所需时间分别是A.t ,2t ﻩﻩ ﻩﻩB.2t,8tC.2t ,2t ﻩﻩﻩ ﻩﻩﻩ ﻩD.t , t11. 图中为一理想变压器,其原线圈与一电压有效值不变的交流电源相连,P 为滑动头。

黑龙江省大庆实验中学2020┄2021学年高二下学期开学考试 英语试题

黑龙江省大庆实验中学2020┄2021学年高二下学期开学考试 英语试题

高二年级英语开学考试试题说明:1. 本套试题答题时间120分钟,总分为150分。

2. 本套试题共分四部分:听力、阅读理解、语言知识运用、写作。

第一部分:听力(共两节,满分20分)第一节(共5小题;每小题1分,满分 5 分)听下面5段对话。

每段对话后有一个小题,从题中所给的A、B、C三个选项中选出最佳选项,并标在试卷的相应位置。

听完每段对话后,你都有10秒钟的时间来回答有关小题和阅读下一小题。

每段对话仅读一遍。

1. What will the woman do on Sunday?A. Show her paintings to the man.B. Eat out with an old friend.C. Go to an art exhibition.2. When does the conversation take place?A. On Thursday.B. On Friday.C. On Saturday.3. What does the man mean?A. He hates to build the bookshelf.B. He has lost the woman’s tools.C. He hasn’t finished his work.4. What did the man go back home to do?A. To get his wallet.B. To wear his jacket.C. To wait for the school bus.5. What will the woman major in?A. Business administrationB. Children’s behavior science.C. Pre-school education第二节(共15小题;每小题1分,满分 15 分)听下面5段对话。

每段对话后有几个小题,从题中所给的A、B、C三个选项中选出最佳选项,并标在试卷的相应位置。

解析黑龙江省大庆实验中学2020┄2021学年高二下学期期中考试英语试题+Word版

解析黑龙江省大庆实验中学2020┄2021学年高二下学期期中考试英语试题+Word版

高二英语试题说明:答题时间120分钟,总分150分。

第I卷第一部分:听力(共两节,满分20分)第一节(共5小题;每小题1分,满分 5 分)听下面5段对话。

每段对话后有一个小题,从题中所给的A、B、C三个选项中选出最佳选项,并标在试卷的相应位置。

听完每段对话后,你都有10秒钟的时间来回答有关小题和阅读下一小题。

每段对话仅读一遍。

1. Why does the man feel awful?A. He can’t find his keys.B. He’s not good at studie sC. He missed many lessons.2. Where does the conversation probably take place?A. In a park.B. At a theater.C. In a parking lot.3. What happened to Tim?A. He knocked someone down.B. He was hit by a motorbike.C. He was seriously ill.4. How many cups did the woman buy online?A. 10B. 20C. 305. What are the speakers supposed to do?A. Watch a performance.B. Visit a museum.C. Buy some books.第二节(共15小题;每小题1分,满分15 分)听下面5段对话或独白。

每段对话或独白后有几个小题,从题中所给的A、B、C三个选项中选出最佳选项,并标在试卷的相应位置。

听每段对话或独白前,你将有时间阅读各个小题,每小题5秒钟;听完后,各小题将给出5秒钟的作答时间。

每段对话或独白读两遍。

请听第6段材料,回答第6、7题。

6. When does the conversation take place?A. In the morning.B. In the afternoon.C. In the evening.7. How long does the man give the woman?A. 30 minutes.B. 20 minutes.C. 10 minutes.请听第7段材料,回答第8、9题。

黑龙江省大庆实验中学2020┄2021学年高二下学期期中试题英语

黑龙江省大庆实验中学2020┄2021学年高二下学期期中试题英语

第一卷第一部分听力(共两节,满分20分)第一节:(共5小题,每小题1分,满分5分)听下面5段对话。

每段对话后有一个小题,从题中所给的A, B, C, 三个选项中选出最佳选项,并标在试卷相应的位置。

听完每段对话后,你都有10秒的时间来回答有关小题和阅读下一小题。

每段对话仅读一遍。

1. What will the woman do on weekends?A. Go to the seaside.B. Read some books.C. Work at the store.2. What’s the relationship between the speakers?A. Boss and employee.B. Doctor and patient.C. Teacher and student.3. How many people will attend the party?A. 115.B. 135.C. 150.4. What can we know from the conversation?A. The woman has been to Paris.B. The man lives in London now.C. The man used to live in Paris.5. What does the man imply?A. He is busy with school.B. He doesn’t like the weather.C. The woman plays tennis perfectly.第二节(共15小题,每小题1 分,满分15分)听下面5段对话或独白。

每段对话或独白后有几个小题,从题中所给的A,B,C三个选项中选出最佳选项,并标在试卷的相应位置。

听每段对话或独白前,你将有时间阅读各个小题,每小题5秒钟;听完后,各小题将给出5秒钟的作答时间。

每段对话或独白读两遍。

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说明:本试卷满分70分,时间40分钟。

第一部分:阅读理解(共两节,满分26分)第一节:(共8小题,每题2分,满分16分)阅读下列短文,从每题所给的A、B、C、D中,选出最佳选项,并在答题卡上将该项涂黑。

AThe summer I turned 16, my father gave me a car, which permitted Hannah and me to drive around Tucson whenever we wanted to.Hannah was my best frie nd. “Hannah’s amazing,” my mother always said. And sure enough, that summer she signed with a modeling agency. She was already doing runway work.One day, Hannah and I went to the movies. On the way home, we stopped at the McDonald’s drive-through, putting the fries on the seat between us to share. “Let’s ride around a while,” I said. It was a clear night, moonlight shone over the desert. Taking a turn too fast, I hit a patch of dirt and fishtailed.French fries on the floor. An impossible amount of blood o n Hannah’s face. They took us in separate ambulances. In the ER, my parents spoke quietly:Best plastic surgeon in the city. End of her modeling career.We’d been wearing lap belts, but the car didn’t have shoulder belts. I’d broken my cheekbone; Hannah’s f orehead had split wide open. What would I say to her?When her mother, Sharon, came into my hospital room, I started t o cry, preparing myself for her anger. She sat beside me and took my hand. “I drove into the back of the car of my best friend when I was your age,” she said, “I destroyed her car and mine.”“I’m so sorry,” I said.“You’re both alive,” she said, “The rest is window dressing.” I started to explain, andSharon stopped me. “I forgive you. Hannah will too.”Sharon’s forgiveness allowed Hannah a nd me to stay friends throughout life. I think of her gift of forgiveness every time I tend to feel angry about something recognized as wrong. And whenever I see Hannah, the scars are a symbol of grace for me.1. What caused the car accident?A. Poor visibility.B. Driving too fast.C. Hitting a patch of dirt.D. Not staying focused.2. Which word can best describe Hannah’s mother?A. Supportive.B. Generous.C. Optimistic.D. Helpful.3. What result did the accident cause to Hannah and the author?A. It worsened their friendship.B. It made both of the two disabled.C. It changed Hannah’s working career.D. It ruined the author’s confidence in driving.4. Which is the best title for the text?A. Lucky SurvivalB. Lifelong FriendshipC. My Best Friend HannahD. Learning to ForgiveBIt happens from time to time that after a whole morning of studying, you are tired in the afternoon. It’s then that you might want to eat something sweet, perhaps a Coke or a chocolate bar to lift your mood. After all, it’s popularly believed that a “sugar rush” gives us energy.But a study published in Neuroscience and Biobehavioral Reviews in April suggests that sugar can make us feel worse rather than boost our moods.The German and UK researchers collected data from 31 studies involving nearly 1,300 adults. They studied the effect of sugar on various aspects of mood, including anger, alertness (警惕性), depression and tiredness.They found that people who have too much sugar become more tired and less alert within an hour, and that these feelings become more intense (强烈的) over time.According to the researchers, when people take in sugar, their blood sugar levels rise rapidly, leading to a burst of energy and a short “feel good” period. However, as they begin to di gest (消耗) the sugar, their blood sugar levels decrease quickly, leading to a bad feeling.To remain on a “high”, people are likely to eat more and more sugar until they become addicted to it. As with caffeine, this prevents the body from relaxing, leaving people feeling tired and less alert.But the study findings needn’t make us think we must give up sweet food altogether. According to the Wo rld Health Organization, it is healthy to have the sugars found naturally in fruit, vegetables and milk, so long as these make up less than 5 percent of daily total energy intake.So the next time you feel tired and can’t concentrate, perhaps you should think twice before you bite into a chocolate bar. Maybe a spot of exercise at midday would be a better idea! Tips for beating afternoon fatigue* Head outside and sit in the daylight for 10 minutes.* Get into the routine of a mid-afternoon cup of tea.* Plan group activities for midday.* Add variety to your routine.5. What does the underlined word “boost” in Paragraph 2 probably mean?A. improveB. harmC. con trolD. change6. How did the people feel after they had sugar in the study?A. They felt relaxed.B. They felt more tired.C. They were more alert.D. They felt energetic.7. What do we learn from Paragraphs 5-6?A. Our mood is connected to our blood sugar levels.B. Taking in more sugar benefits mental health.C. Getting caffeine is another way to relax.D. Sugar and caffeine have the same effects.8. What would be the best title of the text?A. Eating more sugar.B. More sugar, more happiness.C. Better ways to lift your mood.D. Can sugar bring you good mood?第二节(共5小题,每小题2分,满分10分)根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。

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