A.沿水平牽引 B.沿圓周運(yùn)行 C.沿跑道牽引 D.沿斜坡?tīng)恳?/p>
A.0.1m/s B.0.2m/s C.0.3m/s D.0.4m/s
A.12m B.15m C.16m D.18m