单项选择题
Reserve buoyancy is the（）.
A.unoccupied space below the waterline B.volume of intact space above the waterline C.excess of the buoyant force over the gravity force D.difference in the buoyant force in salt and fresh waters
单项选择题 Reserve buoyancy is（）.
单项选择题 Reducing the liquid free surfaces in a vessel reduces the（）.
单项选择题 Owing to the big draft，the ship is not permitted to go alongside until the time of（）.
