Question

In a deep valley on Earth, a person shouting will hear an echo as the sound is reflected off the surrounding mountains. In a similar valley on the Moon, no echo will be heard. This is because ___________________.1the gravitational pull on the Moon is too low2the temperature on the Moon is too low3there is no air on the Moon for the sound to travel through4the mountains on the Moon cannot reflect sound​

Answer 1

Answer:

3. sound need a medium to travel (i.e. air) but there is no air on moon so no echo will be heard there.