Question

ans the following question​

Answer 1

Answer:

Ultrasonic (Frequencies less than 20Hz)

Not in audible range

Answer 2

Explanation:

1=Bats produce ultrasonic sounds

2=Bats can see as well as humans can, but they have evolved a sophisticated method of using sound that enables them to navigate and find food in the dark called echolocation. Bats produce echolocation by emitting high frequency sound pulses through their mouth or nose and listening to the echo.

3=echo is a reflection of sound that arrives at the listener with a delay after the direct sound. ... Typical examples are the echoproduced by the bottom of a well, by a building, or by the walls of an enclosed room and an empty room.