273. A vessel at LAT 21° 32' N, LONG 160° 30' W, heads for a destination at LAT 30° 00' N, LONG 150° 00' E. Determine the true course and distance by Mercator sailing.

Mercator sailing yields a true course of 281 and a distance of 2733 nautical miles. This is determined by calculating the difference of latitude, accounting for longitude differences including crossing 180 meridian, finding the difference of meridional parts, and applying trigonometric relationships to determine the course and distance.