On 25 August your 1926 zone time DR position is LAT 24°17.0' S, LONG 05°47.0' W. At that time, you observe Fomalhaut bearing 117°psc. The chronometer reads 07h 26m 52s, and the chronometer error is 00m 15s fast. The variation is 1.5°E. What is the deviation of the standard magnetic compass?

Correct Answer: Option C — 2.8°W

Applying GMT and Almanac data for Fomalhaut enables calculation of the navigational triangle for true azimuth. Comparing the computed true bearing against the standard compass bearing and factoring in magnetic variation yields the remaining compass deviation of 2.8°W.