单项选择题
In the two stage flash distilling plant, which of the pumps listed is vented to the shell of the second stage in order to remove vapor from the pump suction?（）
A.Condenser circulating water pump B.Feed-water heater drain pump C.Distillate pump D.Air ejector condenser drain pump
单项选择题 The purpose of an oil mist detector in a main propulsion diesel engine is to warn of （）
单项选择题 Permitting a diesel engine fuel oil day tank to run dry can cause （）
单项选择题 Water in the fuel can prevent the engine from starting, prevent it from developing full power, or （）
