You depart LAT 15°48'N, LONG 174°06'E and steam 905 miles on course 090°. What is the LONG of arrival?

Correct Answer: Option B — 170°13'W

Departure longitude adjusted for departure latitude and distance sailed along an easterly parallel utilizes departure formula: Departure = Difference in Longitude $\times$ Cosine(Latitude). Solving for longitude of arrival crossing the 180th meridian yields 170°13'W per standard Mercator navigation practices.