On 12 September your 0736 zone time DR position is LAT 28°34.0'S, LONG 174°49.0'E. At that time, you observe the Sun bearing 084° per standard magnetic compass (psc). The chronometer reads 07h 38m 11s, and the chronometer error is 01m 46s fast. The variation is 11°W. What is the deviation of the standard magnetic compass?

Correct Answer: Option B — 3.2°E

Compute Greenwich Mean Time using chronometer time and error. Obtain Local Hour Angle and Declination from the Nautical Almanac. Apply the standard altitude-azimuth formula from Bowditch to determine true bearing. Compare true bearing with compass bearing, accounting for variation, to resolve standard magnetic compass deviation.