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單項選擇題

Black smoke coming from a boiler can be caused by （）.

A.low water level
B.high water level
C.excessively high fuel pressure
D.low oil temperature

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單項選擇題

If a bilge pump failed to build up discharge pressure, you should check for （）.

A.excessive water in the bilges
B.a clogged suction strainer
C.oil in the bilges
D.All of the above

單項選擇題

The shaft and spare parts（） should be well greased in order to avoid corrosion.

A.in the store room
B.in the cylinder
C.in the scavenge air box
D.in the water box

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