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问题 单项选择题

原始记录改错应在有错的数据或记录上画一条横线，并在旁边写上正确的数据。原始数据改错率应（）。

A.≤0.5%

B.≤1%

C.≤2%

D.不限制，但改错后因签名或盖章

答案

参考答案：B

完形填空

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口号中词语的正确形式填空。

There once lived a boy named Woo Sing,   小题1:  father brought home a mirror. Woo Sing had never seen one before. So when he saw it for the first time, he didn’t understand   小题2: it was, but thought he saw   小题3:  boy, which made him very happy, for he thought the boy had come to play with him. He spoke to the stranger in a very friendly way, but received no reply. He laughed and waved at the boy, who did exactly   小题4:  same thing. Then he thought, “I’ll go closer. It may be that he doesn’t hear me”. But when he began to walk, the other boy imitated（模仿）him. Woo Sing stopped   小题5:  (think) about these strange actions, saying to himself, “This boy is fooling me. He does everything that I do;” and the more he thought about it, the   小题6:  (angry) he became and soon he noticed the boy became angry too. So Woo Sing  小题7:  (strike) the boy in the glass, but he only hurt his own hand and went  小题8: (cry) to his father, who said, “The boy you saw was  小题9:  image. This should teach you an important lesson, my son. You should never show your anger to others. Now remember that in real life when you strike   小题10: cause you’ll hurt yourself most of all.” 
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问答题

如图所示，水平传送带以不变的速度v向右运动，将工件轻轻放在传送带的左端，由于摩擦力的作用，工件做匀加速运动，经过时间t，速度变为v；再经时间2t，工件到达传送带的右端，求：

（1）工件在水平传送带上滑动时的加速度

（2）工件与水平传送带间的动摩擦因数

（3）工件从水平传送带的左端到达右端通过的距离
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