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问题 选择题

如图所示为推行节水工程的转动喷水“龙头”，水平的喷水“龙头”距地面高为h，其喷灌半径为可达10h，每分钟喷出水的质量为m，所用的水从地下H深的井里抽取，设水以相同的速率喷出，水泵的效率为，不计空气阻力（重力加速度为g）,则                 （   ）

A．喷水龙头喷出水的初速度为

B．水泵每分钟对水所做的功为

C．水泵每分钟对水所做的功为

D．带动水泵的电动机的最大输出功率为

答案

ABD

填空题

缺词填空

1. Can you give me some __________(建议) about learning math?

2. Kate often feels __________(紧张不安的) when she talks to me.

3. I like history,but I don't like __________(地理).

4. There are many __________(语言) in the world. Most of them aren't used widely.

5. Do you know the __________(长) of the Yellow River?

6. Do you like your trip? Is it __________(令人愉快的).

7. The girl with long hair is the __________(苗条的) of the three.

8. Liu Xiang and Yao Ming are both myh __________. Do you agree with me?

9. We don't know this song very well because it's __________.

10. He is __________(like to give money or things to others)to his friends.
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选择题

日本侵略者在其占领区宣传“中日亲善”、“共存共荣”的根本目的是（ ）

A．缓和中日民族矛盾

B．欺骗世界舆论

C．引诱国民党投降

D．使中国人民顺从其统治
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