Question

what is echo?............​

Answer 1

Answer:

In audio signal processing and acoustics, echo is a reflection of sound that arrives at the listener with a delay after the direct sound. ... Typical examples are the echo produced by the bottom of a well, by a building, or by the walls of an enclosed room and an empty room.

Answer 2

Answer:

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→ Repetition of sound by reflection of sound waves is known as echo.