单项选择题
A.power-driven vessel dead in the water
B.sailing vessel on the port tack
C.vessel not under command
D.vessel fishing with nets
单项选择题 In order to maintain speed while changing course from a close reach to a broad reach，the sails should be（）.
单项选择题 In order for a vessel to be engaged in fishing she must be（）.
单项选择题 In fog you observe your radar and determine that risk of collision exists with a vessel which is 2 miles off your port bow. You should（）.