单项选择题
The downflooding angle for a ship is the minimum angle at which（）.
A.the load line becomes submerged B.a non-watertight opening is at still water level C.offset becomes excessive D.reserve buoyancy is a maximum
单项选择题 The difference between the height of the metacenter and the height of the center of gravity is known as the（）.
单项选择题 The difference between the forward and aft drafts is（）.
单项选择题 The center of flotation of a vessel is the point in the waterplane（）.
