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
The extension of the after part of the keel in a single-screw vessel upon which the stern post rests is called the（）.
In nautical terminology a dog is a（）.
The function of the bypass valve on the self-contained breathing apparatus is to（）.
As oil pipe line connections were broken，（）quantity of oil was caused to spill onto the wharf and into the dock water.
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（）.
Cargo pump relief valves are piped to the（）.
An integral part of a blowout preventer that serves as the closing element on an open hole，and whose ends do not fit around the drill pipe but seal against each other and shut off the space below completely is the（）.
The most common type of davit found on merchant vessels today is the（）.
In the piping systems of a vessel，what type of valve gives the least resistance to fluid flow when fully open?（）.
The portable radio apparatus means（）.