问题 实验题

(双选)关于打点计时器的原理和使用方法,下列说法中正确的是       

A.打点计时器应接交流电源,交流电频率通常为50Hz

B.如果纸带上相邻两个计数点之间有四个点,则相邻两个计数点间的时间间隔是0.08s

C.如果打点计时器在纸带上打下的点先密集后稀疏,则说明纸带的速度是由小变大

D.电磁打点计时器接在220 V电源上,电火花打点计时器接在6 V电源上

答案

AC

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Symbol of friendship

Friendship is a wonderful thing to have no matter how old you are. However, it is important for teens and young adults to provide conversation, support and so much more as friends.    小题1:__  Actually, there are a few things that symbolize a friendly relationship.

 小题2: 

One of the symbols of a wonderful relationship between friends is easy conversation. When you can talk about almost anything, you are sure to be true friends. When the conversation flows easily from one topic to another, this can be a symbol of friendship as well.

Able to have fun 

 小题3:  No matter what you are doing, you can have a fun experience so long as you are with your friend. This is one of the best parts of friendship.

Support all the time

If your friends know they can call you anytime and you will be there for them, then this symbolizes friendship.

Attentive (专心的) listening by both individuals

If you find that you listen closely to what your friend says and they do the same for you, this is another symbol of friendship.   小题4: 

Share laughter and tears

Another symbol of friendship is the ability to share both laughter and tears. A friend is someone with whom you can laugh and cry over anything.   小题5: 

A.You feel comfortable with this person to share your special feelings.

B.Easy conversation

C.A true friend is someone you can have a great time with.

D.Teenagers always have difficulty in making friends.E. Get together

F. True friends listen closely to each other and understand what the other person is saying.

G. If you are trying to make friends, you may be wondering what symbolizes friendship.

选择题