While navigating in fog off a coastline of steep cliffs, you hear the echo of the ships fog horn 2 1/2 seconds after the signal was sounded. What is the distance to the shore?

Correct Answer: Option B — 460 yards

Using the speed of sound at 1,100 feet per second, a 2.5-second round-trip echo indicates the sound traveled for 1.25 seconds to reach the cliff. 1.25 seconds multiplied by 1,100 feet per second equals 1,375 feet. Dividing 1,375 by 3 feet per yard yields approximately 458.3 yards, rounding to 460 yards.