A vessel at LAT 32°14.7'N, LONG 66°28.9'W, heads for a destination at LAT 36°58.7'N, LONG 75°42.2'W. Determine the distance by Mercator sailing.

Correct Answer: Option A — 538.2 miles

Mercator sailing uses the difference in latitude and the difference in longitude to find the departure and distance. Using the formula: distance = (diff Lat) / cos(mean course), or more accurately, the meridional parts method, the calculation yields a distance of 538.2 miles between the two specified geographic coordinates.