典型的荧光灯电子镇流器不构成其功能电路的是() A.整流滤波电路 B.启动电路 C.

题型:单项选择题

问题:

典型的荧光灯电子镇流器不构成其功能电路的是()

A.整流滤波电路

B.启动电路

C.低频自激电路

D.灯管谐振电路

考点:电工特种作业操作证电工复审电工复审题库
题型:单项选择题

换流阀的损耗主要包括()。

A.通态损耗

B.关断损耗

C.阻尼回路损耗

D.阀电抗器损耗

题型:单项选择题

电动机是把______能转化为机械能的机器.

题型:单项选择题

空气制动装置包括()制动两大部分。

题型:单项选择题

阅读理解。

     I suddenly heard an elephant crying as though frightened. Looking down, I immediately recognized that

something was wrong, and ran down to the edge of the near bank. There I saw Ma Shwe with her three-

month-old calf struggling in the fast-rising water and it was a life-and-death struggle. Her calf was floating

and screaming with fear. Ma Shwe was as near to the far bank as she could get, holding her whole body

against the rushing water and keeping the calf pressed against her huge body. Every now and then the rushing

water would sweep the calf a way.

     There was a sudden rise in the water and the calf was washed clean over the mother's body and was

gone. Ma Shwe turned quickly to reach it and pressed the calf with her head and trunk (象鼻) against the

rocky bank. Then with a huge effort she picked it up in her trunk and tried until she was able to place it on

a narrow shelf of rock

     Just at this moment she fell back into the river. If she were carried down, it would be certain death. I

knew as well as she did, that there was one spot (地点) where she could get up the bank, but it was on the

other side from where she had put her calf

     While I was wondering what I could do next, I heard the sound of a mother's love. Ma Shwe had crossed

the river and got up the bank and was making her way back as fast as she could roaring (吼叫) all the time

but to her calf it was music.

1. The moment the author got down to the river bank he saw ____.

A. the calf was about to fall into the river

B. Ma Shwe was placing the calf on the rock

C. the calf was washed away by the rising water

D. Ma Shwe was holding the calf against the rushing water

2. How did Ma Shwe manage to save her calf from the fast-flowing water?

A. By putting it on a safe spot

B. By pressing it against her body

C. By taking it away with her

D. By carrying it on her back

3. How did the calf feel about the mother elephant's roaring?

A. It was a great comfort

B. It was a sign of danger

C. It was a call for help

D. It was a musical note

4. What can be the best title for the text?

A. A Mother's Love

B. A Brave Act

C. A Deadly River

D. A Matter of Life and Death

题型:单项选择题

在制作形状渐变动画时,在属性栏中会有一个混合选项,当我们调节这个混合选项时,发现动画并没有发生变化,这可能是因为()

A.因为这个选项要在两个关键帧上均有两个图形才可以起作用

B.因为这个选项最少在某一帧上有两个图形才可以起作用

C.这个选项只针对于其他动画,对形状渐变动画不起作用

D.这个选项要由三个帧制作的形状渐变动画起作用

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