单项选择题
The Plimsoll mark on a vessel is used to（）.
A.align the vessel's tailshaft B.determine the vessel's trim C.determine the vessel's freeboard D.locate the vessel's centerline
单项选择题 The difference between the starboard and port drafts due to wind or seas is called（）.
单项选择题 The difference between the starboard and port drafts caused by shifting a weight transversely is（）.
单项选择题 The change in trim of a vessel may be found by（）.
