A.They are less expensive
B.They are smaller for equivalent pumping ability
C.They pump more cargo in less time
D.All of the above
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A.cargo pump pressure gauges
B.crossover lines interconnecting two pumps
C.suction side of pumps
D.atmosphere through pump vents
A.advance
B.cavitation
C.edging
D.slip
A.a not knowing
B.an unknowing
C.an unknown
D.a not known
A.brake
B.devil's claw
C.pawls
D.All of the above
A.sand
B.soft soil
C.stiff clay
D.heterogeneous soil
最新試題
As the propeller turns，voids are formed on the trailing and leading edges of the propeller blades causing a loss of propulsive efficiency，pitting of the blades，and vibration. These voids are known as（）.
On a ship，a door that is required to be marked KEEP CLOSED is designed to（）.
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Centrifugal pumps have what advantage(s) over reciprocating pumps?（）.
The exhaust pipe must be gas tight throughout its entire length otherwise（）.
Cargo pump relief valves are piped to the（）.
The connected joints of pipe，usually made of three joints of pipe approximately 90 feet long，racked in the derrick when making a trip are called a（）.
All electrical appliances aboard a vessel should be grounded to（）.
The purpose of a bilge well is to（）.
If the engine of a survival craft does not start，check to see（）.