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问题 计算题

汽车以v0=10m/s的速度在水平路面上匀速运动，刹车后经2秒速度变为6m/s，求：

（1）刹车过程中的加速度；

（2）汽车在运动最后2秒内平均速度。

答案

（1）

（2）汽车匀减速末速度为零，可以也它的运动反过来作为初速为零的匀加速处理

  

单项选择题

在Q国生产的收音机的成本比Y国生产的收音机的成本少10%。即使把运输费和关税加上，一个公司将收音机从Q国进口到Y国仍比在Y国生产的收音机便宜。
以上陈述如果是正确的，最有力地支持了以下哪一个论断( )

A．Q国的劳动力成本比Y国低10%。

B．从Q国进口收音机到Y国将减少Y国的制造业10%的就业机会。

C．对从Q国进口到Y国的收音机征收的关税少于在Y国制造该收音机成本的10%。

D．将收音机从Q国运到Y国的运费大于在Q国制造该收音机成本的10%。
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填空题

语法填空：阅读下面短文，按照句子结构的语法性和上下文连贯的要求，在空格处填入一个适当

的词或使用括号中词语的正确形式填空。

     One Sunday morning in August I went to local music festival. I left it early because I had an appointment

1______ (late) that day. My friends walked me to the bus stop and waited with me 2______ the bus arrived.

I got on the bus and found a seat near the back, and then I noticed a man 3______ (sit) at the front. He 

4______ (pretend) that a tiger toy was real and giving it a voice. He must be 5______ (mental) disabled.

     Behind him were other people to 6______ he was trying to talk, but after some minutes 7______ walked

away and sat near me, looking annoyed.

     I didn't want to be laughed at for talking to him but I didn't like leaving him 8______ his own either.

     After a while I rose from my seat and walked to the front of the bus. I sat next to the man and introduced

myself. We had 9______ amazing conversation. He got off the bus before me and I felt very happy the rest

of the way home.

     I'm glad I made a choice. It made 10______ of us feel good.

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