Celestial Navigation · Time — Arc to Time
Convert a longitude of 90°W to time (15° = 1 hour).
- A5h 00m
- B6h 00m✓ Correct
- C9h 00m
- D4h 30m
Explanation
90° ÷ 15 = 6 hours exactly. West longitude is behind Greenwich in time.
Authority: Nautical Almanac, Arc-to-Time table
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