Question

a. What is an echo? ​

Answer 1

Answer:

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Answer 2

Answer:

Echo:-

An echo is a repetition or imitation of sound. When sound waves hit a hard surface they might reflect, making the sound bounce and repeat. ... You were frightened when you thought someone was following you, until you realized you were only hearing the echo of your own footsteps.

Explanation:

example of echo is the repeating of a sound created by footsteps in an empty marble hallway.