The Light List shows that a navigational light has a nominal range of 12 miles and a height above water of 25 feet (7.6 meters). Your height of eye is 38 feet (11.6 meters) and the visibility is 5.5 miles. At what approximate range will you FIRST sight the light?

Correct Answer: Option C — 8.0 miles

The distance of sighting is limited by the lesser of the luminous range or the geographic range. The geographic range is 1.17 times the square root of the heights (25ft and 38ft), totaling 13.0 nm. However, visibility is restricted to 5.5 miles, so the light is sighted at the visibility limit.