快速熔断器是防止晶闸管损坏的最后一种保护措施,当流过( )倍额定电流时,熔断时间小于20ms,且分断时产生的过电压较低。
A.4
B.5
C.6
D.8
参考答案:B
---Bob’s the branches from the tree. Go and for firewood. Bill!
---Do you think I’m really for his kind of work?
A.cut away; cut it up; cut through
B.cut off; cut it down; cut out
C.cut away; cut it up; cut out
D.cut off; cut it down; cut out
数据与信息有什么不同?