Chapter 24, Problem 25PE

Conversations with astronauts on lunar walks had an echo that was used to estimate the distance to the Moon. The sound spoken by the person on Earth was transformed into a radio signal sent to the Moon, and transformed hack into sound on a speaker inside the astronaut’s space suit. This sound was picked up by the microphone in the space suit (intended tor the astronaut’s voice] and sent back to Earth as a radio echo of sorts. If the round-trip time was 2.60 s, what was the approximate distance to the Moon, neglecting any delays in the electronics?