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單項選擇題

Before using a fixed CO₂ system to fight an engine room fire，you must（）.

A.secure the engine room ventilation
B.secure the machinery in the engine room
C.evacuate all engine room personnel
D.All of the above

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單項選擇題

Before a tank is to be crude oil washed，the oxygen content in the tank must be measured at a position（）.

A.immediately above the level of the oil
B.at the top of the tank
C.in the vent riser
D.one meter from the deck

單項選擇題

Backfire flame arrestors are installed on（）.

A.fuel tanks
B.spark plugs
C.carburetors
D.distributors

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