单项选择题
A.in open air B.inside cabins C.in machinery space D.underwater
The storage device for nitrogen-pressurized hydraulic f...
单项选择题The storage device for nitrogen-pressurized hydraulic fluid，which is used in closing the blowout preventers is called the（）.
A.actuator B.annulus C.accumulator D.annular preventer
The shut off valve at the gasoline tank which can be op...
单项选择题The shut off valve at the gasoline tank which can be operated from outside the tank space （）.
A.controls the amount of gasoline to the engine B.shuts off the gasoline supply at the tank C.is used if the gasoline tank leaks D.All of the above
The primary hazard of liquefied petroleum gas and lique...
单项选择题The primary hazard of liquefied petroleum gas and liquefied natural gas is（）.
A.pressure B.toxicity C.temperature D.flammability
