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單項選擇題

Halon extinguishes fire primarily by（）.

A.cooling
B.smothering
C.shielding of radiant heat
D.breaking the chain reaction

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單項選擇題

Halon gas will decompose and may form very hazardous toxic fumes when discharged（）.

A.directly on flames
B.at room temperature
C.in an extremely cold climate
D.None of the above

單項選擇題

Hand hold or straps on the underside of an inflatable are provided（）.

A.to right the raft if it capsizes
B.to carry the raft around on deck
C.for crewmen to hang on to
D.to hang the raft for drying

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