A.Remain B.to remain C.retain D.to retain
A.steam rather than gas is used to turn a shaft B.vapor rather than gas is used to turn a shaft C.the former uses gas to turn a shaft D.the latter uses gas to turn a shaft
A.they operate between 150 and 450 rpm B.they are connected to the propeller by gearing C.their smaller size and weight D.they can be connected directly to the propeller without gearing