The alarm signal for engine room catching fire is a blast of random bell followed by ____. (238885:第5 章国际公约、规则:178)A、 twoB、 three knocksC、 four knocksD、 five knocks-易过题库-题库最全的搜题网站

The alarm signal for engine room catching fire is a blast of random bell followed by ____. (238885:第5 章国际公约、规则:178)

A two

B three knocks