General Navigation USCG Question #2025 (Set 63)

A tide is called diurnal when __________.

Official USCG Answer & Rule Citation

Correct Answer: Option A — only one high and one low water occur during a lunar day

In USCG General Navigation principles (Bowditch, Light Lists, and Coast Pilots), regarding 'A tide is called diurnal when', the verified fact is: 'only one high and one low water occur during a lunar day'.

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