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问题 单项选择题

为从时间上判别断路器失灵故障的存在，失灵保护的动作时间应（）故障元件断路器跳闸时间和继电保护动作时间之和

A.大于

B.等于

C.小于

D.小于或等于

答案

参考答案：A

填空题

根据首字母提示及句意写出单词

1. M__________ is the third month of the year.

2. Next week we'll go to London for a h__________.

3. Don't s__________ in the classroom. Your classmates are doing their homework.

4. -Which is your favourite f__________?

    -Chinese New Year.

5. At Halloween many people wear s__________ costume with masks.
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单项选择题

为方便值班轮休，现将甲、乙两组奥运志愿者服务队拆分成3组，原甲组人数的加乙组人数的值早班；原甲组人数的与乙组人数的值中班；两组剩下共25人值晚班。假定每人每天只值一班，则甲、乙两组原来共有（）人。

A．42

B．48

C．60

D．72
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