A.80~100km/h B.100~l20km/h C.120~140km/h D.140~160km/h
A.轉(zhuǎn)向架兩端 B.轉(zhuǎn)向架中間 C.機車兩端 D.機車中間
A.±2% B.±4% C.±3% D.±1%