A.red flares B.smoke signals C.sound signals D.Any of the above
A.Safety signal B.Urgency signal C.Distress signal D.Red alert signal
A.Directing the beam of a searchlight at another vessel B.A smoke signal giving off orange colored smoke C.A whistle signal of one prolonged and three short blasts D.International Code Signal PAN spoken over the radiotelephone
A.International Code Signal AA B.orange-colored smoke C.red flares D.the repeated raising and lowering of outstretched arms
A.the continuous sounding of any fog signal apparatus B.giving five or more short and rapid blasts of the whistle C.firing a gun at intervals of about a minute D.a barrel with burning oil in it，on deck
