You are Master of a towing vessel engaged in towing three barges astern.The middle barge o

You are Master of a towing vessel engaged in towing three barges astern.The middle barge of the tow would be required to sound which of the following during restricted visibility ().

A.No fog signal

B.A prolonged blast at intervals never to exceed more than two minutes

C.A prolonged blast followed by two short blasts at intervals never to exceed more than two minutes

D.A prolonged blast followed by three short blasts at intervals never to exceed more than one minute

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