General Navigation USCG Question #106 (Set 4)

Under the IALA cardinal system, a mark with quick white light showing 3 flashes every 10 seconds indicates that the safest water in the area is on the __________.

Official USCG Answer & Rule Citation

Correct Answer: Option B — east side of the mark

IALA Cardinal marks utilize light characteristics to indicate safe water. An East Cardinal mark displays a quick or very quick white light with three flashes, corresponding to the mnemonic 'three o'clock' on a clock face. This signifies that the safest water lies to the east of the mark.

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