单项选择题
A.The colder seawater passing through the condenser tube bundles of the various stages increases evaporator vacuum
B.The amount of heated feed water discharged from the feed water heater after cndenser is increased
C.Fewer non-condensable gases are created by the flow of colder seawater
D.More seawater is allowed to pass through the flint stage overflow weir
单项选择题 Moisture is removed from a refrigeration system by（）.
单项选择题 A centrifugal pump vibrates excessively during operationUpon disassembling the pump it is found that the impeller is out of balanceWithout an available spare, you should （）.
单项选择题 An axial piston, variable stroke pump is used in a vessels hydraulic steering gearUnder pressure, oil continually leaks out from between the valve plate/cylinder barrel and will（）.