Each inert gas system gas main must have a
题型：单项选择题
问题：
Each inert gas system gas main must have an automatic shut down valve at the outlet of the gas production plant. This valve must close automatically upon（）.
A.cargo pump failure
B.blower failure
C.deck seal low water level
D.low inert gas temperature
时（T为交流的周期），原线圈中的电流瞬时值为0.03A．变压器的原、副线圈的匝数比为（ ）
：3