单项选择题
A.viscosity B.density C.velocity D.electricity
The pressure of pilot air is usually （） than that of st...
单项选择题The pressure of pilot air is usually （） than that of starting air.
A.higher B.lower C.low D.high
The power generated in the turbine must （） that require...
单项选择题The power generated in the turbine must （） that required by the compressor.
A.be less than B.be larger than C.be as large as D.not be so large as
The position of the piston parts in relation to each ot...
单项选择题The position of the piston parts in relation to each other is secured by means of （） and a dowel pin in the crown.
A.bosses B.through bolts C.machine-turned recesses D.long studs
