A partially full tank causes a virtual rise in the height of the（）.

A.lower than the keel
B.at the same height as the center of gravity
C.exactly at midships
D.at the center of the waterplane area

A.Minerals Management Service
B.Department of Energy
C.Corps of Engineers
D.A recognized classification society approved

A.center of gravity
B.center of buoyancy
C.center of flotation
D.metacenter