You depart LAT 49°45.0'N, LONG 06°35.0'W, and steam 3599 miles on course 246.5°T. What is the longitude of your arrival by Mercator sailing?

Correct Answer: Option C — LONG 77°02.8'W

Mercator sailing uses meridional parts to determine longitude change. Given the distance and course, the difference in latitude is 1479.5' (24°39.5'S). Calculating the difference in meridional parts and applying the formula ΔLong = ΔM × tan(course) yields a longitude change of 70°27.8'W, resulting in 77°02.8'W.