Besides heat, fuel, and oxygen, which

1、Fueling activities（）waste liquids and

Fueling activities（）waste liquids and vapor releases to air.AcommenceBgenerateCgiveDhave

2、The fuel oil pressure and forced draug

The fuel oil pressure and forced draught pressure should be matched to ensure good combustion with a full steady flameIn the sentence the word “match” means （）Ajoin withBmixCbe equal toDbe constant

3、Fuel scarcities and price increases（）a

Fuel scarcities and price increases（）automobile designers to develop completely new lines of small cars and trucks.ApromptedBpersuadedCimposedDenlightened

4、The vapors given off by heated fuel oi

The vapors given off by heated fuel oil are flammable, explosive, and （）Alighter than airBheavier than airCodorlessDnontoxic

5、Heat damage to fuel injection nozzles

Heat damage to fuel injection nozzles can be prevented by avoiding （）Aexcessive fuel oil temperatureBlong periods of engine overloadCmetallic contact between nozzles and cylinder headsDhard carbon deposit and varnish on the nozzle

6、The vapors given off by heated fuel oi

The vapors given off by heated fuel oil are heavier than air and are（）.AodorlessBexplosiveCnontoxicDvisible