单项选择题
A.From every fix or running fix
B.From every estimated position
C.Every three minutes in pilotage waters
D.Only in pilotage waters
单项选择题 You have been informed that dredging operations may be underway in your vicinity.Which buoy indicates the dredging area（）.
单项选择题 You determine your vessel’s position by taking a range and bearing to a buoy.Your position will be plotted as a（n）（）.
单项选择题 Which statement concerning current is TRUE（）.