Recently，these companies have ________ some workers becames of the drop in economy.

A．hired

B．dismissed

C．refused

D．employed

调速器静特性试验的目的是确定转速死区，校验（）。

A.缓冲时间常数

B.永态转差系数

C.暂态转差系数

D.接力器不动时间