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單項選擇題

A donkey boiler is （）.

A.one to supply steam to the main propulsion turbine
B.an auxiliary boiler
C.A and B
D.neither A nor B

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單項選擇題

Safety valves on a boiler vent to the （）.

A.fuel tank
B.bilge
C.atmosphere
D.auxiliary exhaust line

單項選擇題

The boiler feed pump discharge pressure is higher than the steam drum pressure to （）.

A.ensure feed water flow into the boiler
B.keep the steam drum pressure high
C.prevent water hammer in the feed line
D.help the feed water flash to steam