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问题 单项选择题 A1型题

男性，32岁，患肺脓肿，应用青霉素后有明显效果，应持续应用多长时间（）。

A.6～8周

B.2～4周

C.8～12周

D.12～16周

E.4～6周

答案

参考答案：C

填空题

根据首字母或汉语提示完成单词。

1. He has received many g_____ on his birthday.

2. We visit my grandma every Sunday and she always cooks s_____dishes for

us.

3. —Why don't you get a camera?

    —That's too e_____.

4. Tom got a nice bike on his twelfth birthday. What a lucky _____ (家伙)!

5. Can you give me a _____(建议) about what to do today?
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计算题

如图所示，质量不计的光滑木板AB长1.2m，可绕固定点O转动，离O点0.2m的B端挂一重物G，板的A端用一根与水平地面成30°夹角的细绳拉住，木板在水平位置平衡时绳的拉力是6N．然后在O点的正上方放一质量为0.3kg的小球，若小球以25cm/s的速度由O点沿木板向A端匀速运动，问小球至少运动多长时间细绳的拉力减小到零．（取g=10N/kg，绳的重力不计）
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