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问题 选择题

在真空中有两个静止的点电荷，若保持它们的电荷量不变，仅将它们之间的距离减小为原来的，则它们之间的库仑力将

A．增大为原来的2倍

B．减小为原来的

C．增大为原来的4倍

D．减小为原来的

答案

答案：C

题目分析：根据库仑定律的公式 ，各自的电荷量不变，距离减小为原来的，它们之间的距离不变，则库仑力变为原来4倍．故c正确，A、B、D错误．

故选C．

点评：解决本题的关键掌握库仑定律的公式．

单项选择题

麻醉药品和第一类精神药品（）

A．不得零售

B．可以零售

C．不得自行提货

D．可以自行提货

E．不得以健康人为受试对象
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单项选择题

About a week ago, when I was playing basketball at our local park, I noticed a small group of boys picking on a smaller, skinnier boy. They were (21) him names and even pushed him to the ground and kicked dirt in his face. (22) I saw that, I walked over to the group.
I stepped (23) them and the smaller boy, and asked them politely what this boy had done worthy of (24) they were doing to him. One of the boys replied, "He’s weird. " At that, I asked one of the boys if he thought his friend was weird, and the (25) was "No." So, I asked another boy what the word "weird" (26) , and he said, "Different." That was my cue (暗示). I told them that everyone is (27) , and that they all looked just as different to the other boy as he did to them. They all stood (28) for a moment, and then the most amazing thing happened. One of the boys helped the small boy off the ground and then said sorry to him. He (29) to let him play with them.
I thanked the boy for being so (30) As I looked around, I realized that there were dozens of other people at the park (31) no one else had stopped to help this boy. I felt happy that the boy was p enough to stand up against his friends to (32) someone in need, but I felt sad that (33) else had even taken a second look.
I hope that my action helped them (34) that they could have made a difference with a little (35) , and maybe next time they will be the ones who choose to help.

Ⅱ. 完形填空

/Close
通过下面短文，掌握其大意，然后再各题所给的四个选项(A、B、C和D)中选出一个最佳选项。

A．or

B．so

C．and

D．but
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