During evening twilight on 28 December a sextant altitude (hs) of the planet Venus was 29°43.2'. The height of eye was 40 feet, and the index error was 2.0' on the arc. What was the observed altitude (Ho)?

Correct Answer: Option B — 29°34.1'

Per Bowditch, apply corrections to the sextant altitude (hs): subtract index error (2.0') to get observed altitude (ha) of 29°41.2'. Apply dip correction for 40 feet (-6.2') and altitude correction for Venus (-0.9') to reach the final observed altitude (Ho) of 29°34.1'.