单项选择题
The volume of watertight spaces of a vessel above its waterline is the vessel’s（）.
A.free surface B.marginal stability C.reserve buoyancy D.freeboard
单项选择题 The upward pressure of displaced water is called（）.
单项选择题 The total weight of cargo，fuel，water，stores，passengers and crew，and their effects，that a ship can carry，is the（）.
单项选择题 The term that indicates how many tons of cargo a vessel can carry is（）.
