单项选择题
A mixed-flow pump is a （） pump classified by the workin...
单项选择题A mixed-flow pump is a （） pump classified by the working principle.
A.self priming B.positive displacement C.reciprocating D.impeller
The （）pump is usually used as the bilge feed pump to an...
单项选择题The （）pump is usually used as the bilge feed pump to an oily water separator.
A.turbine B.screw C.vane D.ejector
The （）pump is usually used as the emergency bilge pump....
单项选择题The （）pump is usually used as the emergency bilge pump.
