The Light List shows that a navigational light has a nominal range of 6 miles and a height above water of 18 feet (5.5 meters). Your height of eye is 40 feet (12.2 meters) and the visibility is 27.0 miles. At which approximate range will you first sight the light?

Correct Answer: Option C — 9.8 miles

Geographic range is 1.17 * sqrt(18) + 1.17 * sqrt(40), equaling 5.0 + 7.4 = 12.4 nm. Since the visibility is 27 miles, the geographic range is the limiting factor. The light will be sighted at the geographic range, which is approximately 9.8 nm.