logo - 刷刷题
下载APP
【单选题】

熔断器的熔管内充填石英砂的目的是

A.
绝缘
B.
防护
C.
灭弧
D.
散热
举报
参考答案:
参考解析:
.
刷刷题刷刷变学霸
举一反三

【单选题】分级绝缘变压器用熔断器保护时,其中性点必须()。

A.
. 不接地
B.
. 间接接地
C.
. 直接接地
D.
. 直接或间接接地

【单选题】When stars like our Sun die, they bloat to become red giants and then eject gigantic clouds of gas and dust into space. Increasingly, however, scientists found themselves at a profound loss to explain...

A.
explain-the possible way of death of our Sun.
B.
show the two types of red giants.
C.
discuss on the way of red giants to become white dwarfs.
D.
explore the origin of life.