易碎接头是常闭活门。
A.The fragile connector is usually closed.易碎连接器通常是闭合的 B.The quick-break switch is normally in the off position. C.The frangible fitting is a normally closed valve.正确答案C
易碎接头是常闭活门。
A.The fragile connector is usually closed.易碎连接器通常是闭合的 B.The quick-break switch is normally in the off position. C.The frangible fitting is a normally closed valve.正确答案C
