CO2 extinguishes a fire by __________.
A.a blanket of bubbles formed on the surface of the fire
B.smothering
C.isolating the heat from the fuel
D.cooling
According to the passage, which is true about the ocean?A. The waters of the ocean came from rain water.B. The ocean was formed from the, lighter rock materials.C. The vast single ocean formed about 200 million years ago.D. The ocean covered the whole surface of the earth at very beginning.
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The BEST method of applying foam to a fire is to ______.A.spray directly on the base of the fireB.flow the foam down a nearby vertical surfaceC.sweep the fire with the foamD.spray directly on the surface of the fire
The most effective way to apply a foam stream if the fire is on deck or is a runing fire, is to direct the stream ______.A.onto the surface of the burning liquidB.ahead of the burning liquid and bounce it on the fireC.at the base of the burning liquid in a sweeping motionD.just above the surface of the burning liquid
CO2 extinguishes a fire byA.a blanket of bubbles formed on theB.smotheringC.coolingD.isolating the heat from the fuel
Sludge may be formed in the oil in the crankcase of a reciprocating air conditioning compressor as a result of ______.A.refrigerant bubbles in the lube oilB.refrigerant reducing the lube oil viscosityC.oxidation(氧化) of the lube oil from overheatingD.reducing the floc or cloud point of the oil
An ABC dry chemical fire extinguisher would be LEAST effective against a fire in ______.A.a mattressB.spilled liquids such as oil or paintC.high voltage electrical gearD.a trash can
Foam extinguishes a fire by ______.A.shutting off the air supplyB.cooling the fuel to below ignition temperatureC.dispersing the fuelD.removing the source of ignition
