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问题 选择题

一辆质量为m=1.0×103kg的汽车，经过10s由静止匀加速到速度为30m/s后，关闭油门并刹车，设汽车刹车时所受阻力为车重的0.5倍．则下列选项中正确的有

A．汽车在前10s内的加速度大小为3m/s2

B．汽车在前10s内的加速度大小为10m/s2

C．汽车在关闭油门并刹车后继续滑行的加速度大小为5m/s2

D．汽车在关闭油门并刹车后继续滑行的加速度大小为12m/s2

答案

AC

汽车在前10s内的加速度，A，对，B错

汽车在关闭油门并刹车后继续滑行，根据牛顿第二定律可得，则加速度大小为，C对D错

选择题

选出与画线部分意思相或相近的选项。

1. —Where is he going? 

    —I don't know. [ ]

A. I've no idea

B. I can do nothing

C. I don't thank

D. I know it very well

2. More than ten new students will come to our school. [ ]

A. Over there

B. Over

C. Less than

D. Some

3. Yesterday I reached home very late.[ ]

A. arrived at

B. got

C. arrived in

D. back

4. There are a few oranges in the basket. [ ]

A. some

B. many

C. much

D. a lot of

5. He is a well-known actor. [ ]

A. good

B. outgoing

C. athletic 

D. famous

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单项选择题

慢性支气管炎与肺结核的主要鉴别依据是（）

A．有无发热 

B．有无咳嗽 

C．有无咯血 

D．痰菌检查 

E．支气管造影
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