你可能感興趣的試題

After extinguishing a fire with C02,it is availabe to（）.

A.use all CO₂ available to cool the surronding area
B.stand by with water or other agents
C.thoroughly ventilate the space of CO₂
D.jettison all buring materials

單項選擇題

After putting on a self-contained breathing apparatus, you open the air supply and hear a continuous ringing of a bell.What does this mean?（）.

A.The unit is working properly
B.The face mask is not sealed properly
C.The air bottle needs to be refilled
D.The air supply hose has a leak