问题 选择题
3A的直流电通过电阻R时,t时间内产生的热量为Q;现让一交流电通过电阻R,若2t时间内产生的热量为Q,则该交流电流的有效值和最大值分别为(  )

A.I=3/2A,Im=3A

B.I有=3A,I=3A

C.I有= A,I A

D.I3A,Im=6A

答案

答案:A

完形填空

Everyone needs friends. We all like to feel close to someone. It is nice       a friend to talk, laugh and do things with. Certainly , sometimes we need to be alone. We don’t always want people     

But we would feel        if we never had a friend. No two people are        . Friends sometimes don’t get on well. That doesn’t mean that they       like each other. Most of the time they will make up (言归于好), and become        again.

Sometimes friends move away. Then we feel very       . We miss them very much, but we can       them and write to them. It could be possible that we could even see them again. And we can also        new friends. There’s more good news for people who have friends. They live longer than people who don’t have. Why? It could be that they are        . Being happy helps you stay well and it could be good just knowing that someone cares about you.

小题1:A. have              B. to have                C. having  

小题2:A. around            B. away                  C. all over  

小题3:A. happy             B. lonely                 C. badly

小题4:A. different           B. kind                  C. the same 

小题5:A. no longer          B. not any longer          C. not  

小题6:A. friends            B. good                  C. pleased 

小题7:A. angry             B. sad                   C. happy    

小题8:A. call               B. ask                   C. tell     

小题9:A. know             B. find                   C. make   

小题10:A. happier           B. stronger               C. kinder  

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