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问题 填空题

放在通电螺线管内部中间处的小磁针，静止时N板指向右端，则电源的C端为     极。   

   

答案

正（＋） 

小磁针静止时N极的指向，为该点磁场方向，螺线管内部磁场方向是从S极到N极，所以螺线管右端为N极，根据右手螺旋定则可知电源的C端为正极

故答案为：正

听力题

根据短文内容及首字母提示,补全空格内单词，使短文完整、通顺

Every one of us, rich or poor, should at least have one or two f       . My friends will l       

to me when I want to speak, will take care of me when I am s       , and my friends will go together with me in our f        time.

Friendship（友谊） is a kind of t        in our lives. It is l        a cup of tea. When we are thirsty（口渴）, it will be our b        choice(选择). But when we have enough time to enjoy o       , it is also like the most w        drink. We can l        together, talk together and even cry together.
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单项选择题

义务教育阶段综合实践活动课程，每周平均为______。

A．1课时

B．2课时

C．3课时

D．4课时
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