单项选择题
The geometric center of the waterplane area is called the（）.
A.center of buoyancy B.center of gravity C.metacenter D.center of flotation
单项选择题 Semisubmersibles A and B are identical. However，A is more tender than B. This means that A relative to B has a（）.
单项选择题 If the cause of severe list or trim is off-center ballast，counterflooding into empty tanks will（）.
单项选择题 The original equilibrium position is stable when（）.
