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问题 不定项选择

如图所示，质量为m的木块在质量为M的长木板上滑行，长木板与地面间动摩擦因数为μ1，木块与长木板间动摩擦因数为μ2，若长木板仍处于静止状态，则长木板受地面摩擦力大小一定为

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A．μ1(m1+m2)g

B．μ2mg

C．μ1mg

D．μ2mg+μ1mg

答案

答案：B

单项选择题 A1型题

急性心力衰竭伴快速房颤的病人首选的治疗是（）

A.控制呼吸道感染

B.控制心室率

C.纠正电解质紊乱

D.控制液体人量

E.加强利尿
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阅读理解
Disposing of the garbage we produce every day is a major problem in cities around the world. In the United States, over 160 million tons of garbage is produced every year. Ten percent is recycled, ten percent is burned, and the rest is put in landfills. But finding land for new landfills is becoming more difficult.
A city that has solved this problem in an unusual way is Machida in Tokyo. They have developed a totally new way of dealing with garbage. The key to the operation is that people should work together. Families must divide their garbage into six groups:
1. garbage that can be easily burned, such as kitchen and garden trash
2. garbage that doesn’t burn easily, such as plastic tools and plastic toys
3. products that are poisonous or that cause pollution, such as batteries
4. bottles and glass containers that can be recycled
5. metal containers that can be recycled
6. large items, such as furniture and bicycles
    The items in Groups 1 to 5 are collected on different days. Large items are only collected upon request. Then the garbage is taken to a centre that looks like a clean new office building or hospital. Inside the centre, special equipment is used to sort and deal with garbage. Almost everything can be reused: garden or kitchen trash becomes fertilizer; garbage that can burn is burned to produce electricity; metal containers and bottles are recycled; and old furniture, clothing, and other useful items are cleaned, repaired, and resold cheaply or given away. The work provides employment for the disabled and gives them a chance to learn new skills.
Nowadays, officials from cities around the world visit Machida to see whether they can use some of these ideas and techniques to solve their own garbage problems.
小题1: Each year people in the U.S.A. have to find places to put in _______ million tons of garbage.
A.160           B.128               C.16                    D.32
小题2:George’s family has the following garbage: wooden chairs, empty tins and branches. Into which group should he put the garbage?
A．Group 6, Group 5, Group 1.B．Group 1, Group 3, Group 2.
C．Group 6, Group 5, Group 2. D．Group 6, Group 4, Group 1.
小题3: From the text we know that ________ .
A．those who are working at the garbage disposal centre are disabled persons.
B．without people’s cooperation, the garbage disposal project would be a failure.
C．the items in Group1 and Group6 are not collected on the same day.
D．the garage is taken to a clean new office building for disposal.
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