单项选择题
A.such risk shall be deemed to exist B.such risk shall not be deemed to exist C.you needn't take any action to avoid collision with any vessel D.you should accelerate your speed ahead
A.one short blast B.one prolonged blast C.two short blasts D.three short blasts
A.In positions in which the noises in the ship are least likely to interfere with the hearing of a fog signal and the man can see clearly B.In positions in which the noises in the ship are much likely to interfere with the hearing of a fog signal C.In positions in which the hearing of a signal is reduced to a minimum D.In a position in which the man can see clearly