单项选择题
A fire of escaping liquefied flammable gas is best extinguished by（）.
A.cooling the gas below the ignition point B.cutting off the supply of oxygen C.stopping the flow of gas D.interrupting the chain reaction
单项选择题 A fire starts on you vessel while refueling. You should first（）.
单项选择题 A flame screen（）.
单项选择题 A foam-type portable fire extinguisher is most useful in fighting a fire in（）.
