单项选择题
A.foam extinguishers B.water spray equipment C.dry powder extinguishers D.soda-acid extinguishers
Class B fires are best extinguished by smothering, i-e（...
单项选择题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
Class A fires are best extinguished by quenching or coo...
单项选择题Class A fires are best extinguished by quenching or cooling with （）.
A.deprival of oxygen B.a water spray C.soda-acid D.foam
A fire starts when the following （） factors come togeth...
单项选择题A fire starts when the following （） factors come together.
A.combustible material B.ignition source C.oxygen D.A and B and C
