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單項選擇題Starting air for auxiliary engines may be taken directly from the main reservoirs or through （）.

A.an auxiliary reservoir
B.a controlling air bottle
C.an emergency air compressor
D.a main air compressor

1.單項選擇題Two main lubricating oil pumps are usual and are obligatory in （）.

A.container ships
B.bulk carriers
C.passenger ships
D.barges

2.單項選擇題In motor-ships, （）, after passing through main and motion bearings and oil cooled pistons, etcis either retained in the bedplate.

A.the fuel oil
B.the lubricating oil
C.the refrigerating oil
D.the hydraulic oil

3.單項選擇題In motorships，there are two main circuits, （）.

A.one salt water, one fresh water
B.one salt water, one fuel
C.one fresh water, one fuel
D.one steam, one fuel

4.單項選擇題Auxiliary machinery covers everything onboard except （）.

A.main engines
B.main boilers
C.pipes and fittings
D.A and B

5.單項選擇題A （）, sometimes called filters, is a device designed to prevent the passage of unwanted solids into the system.

A.steam trap
B.check valve
C.separator
D.strainer