单项选择题
For an upright vessel，draft is the vertical distance between the keel and the（）.
A.waterline B.freeboard deck C.plimsoll mark D.amidships section
单项选择题 For a floating vessel，true mean draft is always the（）.
单项选择题 Deballasting a double bottom has what affect on KG?（）
单项选择题 Although KG for a ship in lightweight is relatively high，the vessel is stiff because（）.
