单项选择题
The abbreviation "GM" is used to represent the （）
A.height of the metacenter B.fighting arm C.righting moment D.metacentric height
单项选择题 A segregated ballast system is a system where （）
单项选择题 A vessel is required to carry an Oil Record Book Part I to log entries in the book regarding the （）
单项选择题 An oil in water monitor is required in order to measure （）
