A.15km/h B.5km/h C.10km/h D.3km/h
A.一長(zhǎng)聲 B.二長(zhǎng)聲 C.三長(zhǎng)聲 D.四長(zhǎng)聲
A.門故障 B.門關(guān)閉 C.門打開 D.門隔離