A.crow bar
B.device to force a water tight door against the frame
C.heavy steel beam
D.wedge
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A.that the fuel valve is open
B.if the air supply system is open
C.if the water sprinkler system is open
D.if the limit switch is on
A.a defective ignition system
B.low lube oil level
C.weak valve springs
D.too heavy a load
A.once each crankshaft revolution
B.twice each crankshaft revolution
C.every other crankshaft revolution
D.every fourth stroke
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
A.cargo pump pressure gauges
B.crossover lines interconnecting two pumps
C.suction side of pumps
D.atmosphere through pump vents
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（）.
Anchors are prevented from running out when secured by the（）.
Limit switches are used on which davits?（）
On a ship，a door that is required to be marked KEEP CLOSED is designed to（）.
In the piping systems of a vessel，what type of valve gives the least resistance to fluid flow when fully open?（）.
The series of valves used to control the return flow in well control operations is called the（）.
An example of a messenger is a（）.
Static electricity may be built up by the（）.
All electrical appliances aboard a vessel should be grounded to（）.
As oil pipe line connections were broken，（）quantity of oil was caused to spill onto the wharf and into the dock water.