Answer:
Step-by-step explanation:
We shall apply Doppler's effect here .
original frequency = 79.79 kHz
apparent frequency due to movement of source ( bat ) = 81.63 Hz
Let the velocity of bat be v .
expression for apparent frequency can be given as follows
n =

n is apparent frequency , n₀ is original frequency , V is velocity of light and v is velocity of source of sound
Putting the values
81.63 =

340-v = 332.33
v = 7.67 m /s
velocity of bat is 7.67 m /s .