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單項選擇題

Class B fires are best extinguished by smothering, i-e（）.

A.deprival of oxygen
B.removal of heat
C.spraying of water
D.injecting of soda-acid

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單項選擇題

Class A fires are best extinguished by quenching or cooling with （）.

A.deprival of oxygen
B.a water spray
C.soda-acid
D.foam

單項選擇題

A fire starts when the following （） factors come together.

A.combustible material
B.ignition source
C.oxygen
D.A and B and C