Sour crude oil（）.

单项选择题Releasing oil from the sea anchor of a survival craft may（）.

A.keep the propeller from being fouled
B.increase propeller speed
C.help calm the waves in the vicinity of the craft
D.increase the holding power of the sea anchor

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