能产生大量蒸汽、气体、粉尘等工作场所和有爆炸危险的工作场所应分别使用( )电器设备。
A.密闭式、防爆型 B.密闭式、密闭型C.防爆式、防爆型 D.防爆式、密闭型
参考答案:A
毡呢(由化纤制作,未浸渍、涂布、包覆或层压)
The level of the river ___ 20 centimeters over the security line and ____must be taken to control the flood.
A.is measured; measures
B.measures; measurement
C.measures; measures
D.is measured; measurement