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2．如图17所示，将质量M=1.20 kg的小沙箱，用轻质软绳（不可伸长）悬挂起来，开始处于静止状态，绳的长度l=0.80 m。用枪向沙箱发射质量m=0.05 kg的子弹，子弹以v0=100 m/s 的速度向右水平击中小沙箱，并留在小砂箱中，小沙箱沿竖直面向上摆动。假设沙箱每次向左运动到最低点时就恰好有一颗同样速度的子弹射入沙箱，子弹射入沙箱的过程时间极短，可忽略不计，重力加速度g取10 m/s2，不计空气阻力。
（1）求第一颗子弹射入沙箱的过程中子弹对砂箱的冲量大小；
（2）求第一颗子弹射入沙箱并相对沙箱静止的瞬间，求砂箱对绳的拉力的大小；
（3）求第一颗子弹射入沙箱后，砂箱摆动的最大高度；
（4）要使沙箱摆动的最大角度小于60°，射入沙箱的子弹数目至少为多少
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翻译 (共7小题，20空；每空0.5分，满分10分)
16. 当地政府必须努力改善当地的经济以赢回民众的信心。
The local government must try hard to improve the economy so as __________ _________ _________ public confidence.
17. 奥巴马出生在夏威夷，是由母亲和祖父母抚养成人的。
Born in Hawaii, Obama was ____________ ____________ ____________ his mother and grandparents.
18. 他们将大量的二氧化碳释放到大气层中，这阻止了地球上的热不能释放到太空中去。 They are putting too much carbon dioxide into the atmosphere, __________ __________ heat __________ escaping from the earth into space.
19. 任何人不可能犯了罪而逃脱处罚。
Nobody can __________ __________ __________ breaking the law.
20. 数以万计的人为了捍卫独立献出了自己的生命。
Hundreds of thousands of people lost __________ lives ____________ __________ of independence.
21. 我们每个人都渴望能考上大学。
Each of us __________ __________ to __________ the college entrance examination.
22. 我信中提到的那个大学生已经报名去西部支教了。
The college student I __________ __________ in the letter has entered for teaching in the west of China.
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16. 当地政府必须努力改善当地的经济以赢回民众的信心。
The local government must try hard to improve the economy so as __________ _________ _________ public confidence.
17. 奥巴马出生在夏威夷，是由母亲和祖父母抚养成人的。
Born in Hawaii, Obama was ____________ ____________ ____________ his mother and grandparents.
18. 他们将大量的二氧化碳释放到大气层中，这阻止了地球上的热不能释放到太空中去。 They are putting too much carbon dioxide into the atmosphere, __________ __________ heat __________ escaping from the earth into space.
19. 任何人不可能犯了罪而逃脱处罚。
Nobody can __________ __________ __________ breaking the law.
20. 数以万计的人为了捍卫独立献出了自己的生命。
Hundreds of thousands of people lost __________ lives ____________ __________ of independence.
21. 我们每个人都渴望能考上大学。
Each of us __________ __________ to __________ the college entrance examination.
22. 我信中提到的那个大学生已经报名去西部支教了。
The college student I __________ __________ in the letter has entered for teaching in the west of China.
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高三毕业前夕，针对现在很多同学报考大学倾向于选择大城市这一现象，你们班进行了一场辩论。内容见下表。请根据表格内容写一封信给21世纪报，介绍辩论情况，并适当发表自己的观点。词数100左右。开头和结尾已给出，不计入总词数。
| 赞成者 | 反对者 | 你的观点 |
| 1、 有更多的发展机会； 2、 交通便利； 3、 生活质量高； 4、 工资水平高。 | 1、竞争激烈、压力大； 2、交通拥挤； 3、空气污染严重； 4、生活成本高。 | ？ |
Dear Editor,
As you know, …
__________________________________________________________________________________________________________________________________________
Yours,
Li Ping
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阅读下面的短文，然后按照要求写一篇150词左右的英语短文。
Heath and climate scientists have mapped how climate change affects different parts of the world in different ways．The scientists point out to evidence that changes in the past thirty years many already be affecting human health．Temperature changes may also influence the spread of disease．For example, warmer weather speeds the growth of organisms that cause diseases like malaria(疟疾)and dengue fever(登革热)．
The work by scientist from the University of Wisconsin-Madison and the World Health Organization appeared in the Journal Nature．Jonathan Patz, professor of the Gaylord Nelson Institute, led the study．He notes that climate scientists linked global warming to the heat that killed thousands in Europe in August of 2003．he says poor countries are least responsible for the warming yet are most at risk from the health effects of higher temperatures．He says areas at greatest risk include Southern and Eastern Africa and coastlines along the Pacific and Indian Oceans．Also, large cities experience what scientists call a”heat island” effect that can intensify(加强)conditions．
Professor Patz says average temperatures worldwide have increased about one-third of a degree Celsius(摄氏的)in the last thirty years．But he tells us even that can make s difference with a disease like malaria．The report says average temperatures could increase by as much as six degrees Celsius by the end of the century．
Representatives from about two hundred nations have been meeting in Montreal, Canada, to discuss climate change．The ten-day conference ends December ninth．It is the first such United Nations meeting since the Kyoto(京都)Protocol took effect earlier this year．The protocol seeks to reduce the amount of carbon dioxide and other heat-trapping gases released as pollution into air．
[写作内容]
1．概括短文的内容要点，该部分的字数大约60词左右；
2．就“如何阻止地球变暖问题？”这一主题谈谈你的看法，至少包含以下的内容要点，该部分的字数大约90词左右。
对空气有污染的工厂要停厂整改。
控制汽车生产量。
鼓励人们乘公共汽车上班或几个人合坐一部车上班。
尽快生产以太阳能(solar power)为动力的交通工具。
[写作要求]
你可以使用实例或其它论述方法支持你的观点，也可以参照阅读材料的内容，但不要抄袭阅读材料中的句子。