Chart Navigation & Plotting · Position
Latitude is measured 0°–90° north or south from the equator; longitude is measured 0°–180° east or west from the:
- AInternational Date Line
- BPrime (Greenwich) meridian✓ Correct
- CNearest landmass
- DMagnetic north pole
Explanation
Longitude is measured east or west from the prime meridian at Greenwich (0°) to 180°. Latitude is measured north or south of the equator. Together they fix any position on Earth.
Authority: Bowditch, American Practical Navigator (Pub. 9), coordinates
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