A.keep the propeller from being fouledB.increase propel……

单项选择题Reid vapor pressure is（）.

A.exerted by liquid cargo on the sides of a tank
B.exerted by liquid cargo on a cargo hose body
C.the lowest temperature and pressure that will cause a flammable liquid to give off vapors
D.a measurement of the amount of flammable vapors given off by a liquid at a certain temperature

单项选择题Regulations require that tankers handling grade B liquids shall have their cargo pumps separated from all sources of vapor ignition by（）.

A.cofferdams
B.empty cargo spaces
C.gas tight bulkheads
D.areas equipped with power ventilation

单项选择题Regulations require that tank vessels handling grade B liquids shall have their cargo pumps separated from all sources of vapor ignition by（）.

A.cofferdams
B.empty cargo spaces
C.gas tight bulkheads
D.areas equipped with power ventilation

单项选择题Regulations require that pumprooms on tank vessels carrying grade C liquid cargo with machinery spaces below the freeboard deck be ventilated with（）.

A.power ventilation
B.gooseneck vents and flame screens
C.at least two ducts extending to the weather deck
D.a vent header system

单项选择题Regulations require that cargo tanks carrying grades D or E liquids on tank barges be vented with（）.

A.gooseneck vents and flame screens
B.pressure-vacuum relief valves
C.branch vent lines and a vent header
D.forced draft blowers