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问题 判断题

落后国家或者落后企业不可能从事原始创新。

答案

参考答案：错

计算题

（12分）在香港海洋公园的游乐场中,有一台大型游戏机叫”跳楼机”.参加游戏的游客被安全带固定在座椅上,由电动机将座椅沿光滑的竖直轨道提升到离地面40 m高处,然后由静止释放，座椅做自由落体运动。座椅沿轨道自由下落一段时间后,开始受到压缩空气提供的恒定阻力而紧接着做匀减速运动,下落到离地面4.0 m高处速度刚好减小到零,这一下落全过程经历的时间是6 s. 取g="10" m/s2.求:  

(1)座椅被释放后自由下落的高度有多高?

(2)在匀减速运动阶段,座椅和游客的加速度大小是多少?

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填空题
用所给单词填空。
surf, keep, cook, rises, are, know, is, make, have, go, like, help, best, watch, ask
1. Sometimes we ______ food at home. 
2. Would you ______ some pepper with your junk food? 
3. Why do you often ______ him questions? 
4. I ______ the Internet once a day. 
5. The results for "read English books"______ fun. 
6. How often do you ______ to the English corner? 
7. Everyone will ______ you if you need any help. 
8. The sun ______ once a day. 
9. Maybe Jay is the ______ pop star in young people’s eyes.
10. I often______a picnic outside on weekends.
11. Walking can____you in good health.
12. There____some milk in the cup.
13. We often____CCTV news at 7:00 in the evening.
14.______a wish and your wish will come true.
15. What do you_______about her lifestyle?
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