A fuel-air mixture below the lower explosive limit is too（）.

[判断题]In international air cargo transportation， SpecificCommodity Rates are usua

[判断题]In international air cargo transportation， SpecificCommodity Rates are usua

[单选题]lower the gangwayA．调整舷梯B．放舷梯C．收舷梯D．摆动舷梯

[单选题]lower a littleA．升一点儿B．把定C．调整D．降一点儿

[单选题]During the fuel injection period, fuel pressure must exceed cylinder gas pressure to （）.A . ensure penetration and distribution of the fuel in the combustion chamberB . ensure the needle valve is flushed clean during each injectionC . prevent combust

[单选题]Fuel injection systems meter fuel, atomize fuel, and （）.A . create turbulence in the combustion chamberB . aid in completing cylinder scavengingC . inject fuel at the proper timeD . minimize fuel penetration into the cylinder

[单选题]Compressed air is supplied by air compression to （）.A . the air receiversB . the starting valvesC . the cylinder coversD . the distributor

[单选题]Fuel injectors used in heavy fuel oil systems are usually provided with cooling to reduce（）.A . cold corrosion of the nozzlesB . fuel viscosity for better atomizationC . carbon accumulation on the nozzlesD . fuel detonation in the cylinder

[单选题]The lower section of a piston is called the （）.A . landB . skirtC . crownD . plate

[单选题]The depth of the ship below the waterline measured vertically to the lowest part of the hull is calledA．trimB．leanC．draftD．tonnage