单项选择题
Before counterflooding to correct a list，you must be sure the list is due to（）.
A.negative GM B.flooding C.off-center weight D.reserve buoyancy
单项选择题 At an angle of loll，the righting arm (GZ) is（）.
单项选择题 At an angle of loll，the capsizing moment is（）.
单项选择题 At all angles of inclination，the metacenter is（）.
