A great circle crosses the equator at 157°W. It will also cross the equator at what other longitude?

Correct Answer: Option B — 23°E

Great circle equatorial crossings are antipodal, occurring exactly 180° apart in longitude. Subtracting 157°W from 180° provides 23°, and changing the E/W designator gives 23°E, complying with standard navigational great circle geometry.