On 4 July you observe the lower limb of the Sun at a sextant altitude (hs) of 25°29.8'. The index error is 3.1' off the arc. The height of eye is 48 feet (14.6 meters). What is the observed altitude (Ho)?

Correct Answer: Option B — 25°40.2'

Correct hs 25°29.8' by adding 3.1' (off the arc) to get 25°32.9'. Subtract dip for 14.6m (-6.7') and add the July Sun altitude correction (+14.0'). This yields an Ho of 25°40.2'. These steps strictly adhere to the Nautical Almanac's sight reduction tables for observed altitude.