单项选择题
A position that is obtained by applying estimated current and wind to your vessel’s course and speed is a(n)（）.
A.dead reckoning position B.estimated position C.fix D.None of the above
单项选择题 A position obtained by crossing lines of position taken at different times and advanced to a common time is a(n)（）.
单项选择题 A position obtained by applying only your vessel’s course and speed to a known position is a （）.
单项选择题 A line of position is（）.
