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單項(xiàng)選擇題

Before starting a gasoline engine on a motorboat，you should make sure for safety that（）.

A.the gasoline tank is full
B.the bilges，cabins，etc. are thoroughly ventilated
C.you have fresh water on board
D.Each of the above is followed

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單項(xiàng)選擇題

Before entering a tank，always check the vapor content（）a combustible gas indicator.

A.with
B.by
C.of
D.for

單項(xiàng)選擇題

After the initial cleaning of flue gas in an inert gas system the gas is passed through what device for final cleaning?（）.

A.Scrubber
B.Demister
C.Deck water seal
D.Final filter

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