单项选择题
A.Reduce speed to bare steerageway
B.Stop your engines
C.Begin a radar plot
D.All of the above
单项选择题 You are underway in reduced visibility.You hear the fog signal of another vessel about 20° on your starboard bow.Risk of collision may exist.You should（）.
单项选择题 You are underway and approaching a bend in the channel where vessels approaching from the opposite direction cannot be seen．You should sound（）.
单项选择题 You are under sail and overtaking a tug and tow.Which action is correct（）.