A.60-90s B.90-120s C.120-180s D.180-240s
影響倒車沖程的因素有:() Ⅰ排水量、船速、船型、船體污底Ⅱ風(fēng)流、水深、主機(jī)倒車功率Ⅲ、主機(jī)換向的快慢
A.Ⅰ、Ⅱ、Ⅲ B.Ⅰ、Ⅱ C.Ⅱ、Ⅲ D.Ⅰ、Ⅲ