搜题请搜索小程序“爱下问搜题”
问题 单项选择题

线路配置综合重合闸装置且按三相重合闸方式投入，当线路发生永久性单相接地故障时，重合闸动作过程为（）。

A.单相跳闸不重合

B.三相跳闸，延时三相重合，后加速跳三相

C.选跳故障相，瞬时重合单相，后加速跳三相

D.直接跳故障相不重合

答案

参考答案：B

阅读理解

When a light passenger plane flew off course[跑道] some time ago, something was wrong with it and it crashed[坠毁] in the mountains and its pilot was killed. The only passengers, a young woman and her two baby daughters, were unhurt. It was the middle of winter. Snow lay thick on the ground. The woman knew that the nearest village was kilometers away. She couldn’t find anything in the snow but a suit-case[行李箱]. When it grew dark, she turned the suit-case into a bed and put the children inside it, covering[盖] them with all the clothes she could find. During the night, it got terribly cold. The woman kept as near as she could to the children and even tried to get into the case herself, but it was too small. Early next morning, she heard planes flying above and wanted to know how she could send a signal[信号Then she had an idea. She wrote the letters ‘SOS’ in the snow. Luckily, a pilot saw the signal and sent a message by radio to the nearest town. It was not long before a group of people arrived and they took the woman and her daughters to hospital at once.

小题1:Where was something wrong with the plane?

小题2:How many people were in the light passenger plane before it crashed?

小题3:What did the woman make the suit-case into a bed for?

小题4:What did the woman do to ask for help?

小题5:Were the woman and her children saved?
查看答案
单项选择题

口腔健康教育的目的是（）

A.传递口腔健康信息

B.使人们认识到并能终生保持口腔健康

C.吸引人们对口腔健康项目的兴趣

D.保证目标人群对口腔健康项目的参与

E.营造有利于口腔健康的环境
查看答案