单项选择题
A.cause of salt contamination B.location of salt water contamination C.chemical makeup of feed-water D.level of alkalinity in condensate
If the suction pressure at the refrigeration compressor...
单项选择题If the suction pressure at the refrigeration compressor is below normal, the cause can be（）.
A.refrigerant overcharge B.overfeeding by the expansion valve C.a restricted suction strainer D.due to short cycling of the compressor
If the viscosity of the liquid being transferred remain...
单项选择题If the viscosity of the liquid being transferred remains constant as the discharge pressure increases, the rotary pump （）.
A.capacity will increase B.capacity will decrease C.suction pressure will increase D.suction pressure will decrease
On tank vessels equipped with power operated cargo tank...
单项选择题On tank vessels equipped with power operated cargo tank valves, the type of power operator most commonly used is （）.
A.hydraulic B.electric C.steam D.diesel
