What is the approximate geographic visibility of an object with a height above the water of 70 feet, for an observer with a height of eye of 65 feet?

Correct Answer: Option B — 19.0 nm

Geographic range is calculated using the formula 1.17 times the square root of the height in feet. For 70 feet, the distance is 9.8 nm; for 65 feet, it is 9.4 nm. Adding these yields 19.2 nm, which approximates to 19.0 nm in standard USCG navigation tables.