单项选择题
A.will remove all the toxic fumes from the air B.has the greatest cooling ability C.will leave no harmful residue D.completely removes combustible vapors from the air
A large oil fire is best extinguished with（）A.soda acid...
单项选择题A large oil fire is best extinguished with（）
A.soda acid B.foam C.CO2 D.sand
Fires in escaping flammable gas are quickly brought und...
单项选择题Fires in escaping flammable gas are quickly brought under control by（）
A.stopping the flow of gas B.reducing the chemical chain reaction C.increasing the oxygen supply D.cooling below the autoignition point
If a fire occurs in the boiler room because of a leakin...
单项选择题If a fire occurs in the boiler room because of a leaking fuel line to a burner, you shut off the fuel using the（）
A.burner valve B.root valve C.quick closing valve D.oil return valve
