单项选择题
A casualty report of an intentional grounding of a ship is required under what condition?（）
A.Under any condition B.If the grounding lasts over 24 hours C.If it creates a hazard to the environment D.At the owner's discretion
单项选择题 A buoy with a composite group-flashing light indicates a(n)（）.
单项选择题 A block and tackle is “rove to advantage”. This means that the（）.
单项选择题 A ballasted vessel sinks enroute to a dry dock. Under these circumstances，the vessel’s owner can claim（）.
