Answer:
The speed of the bat is 5.02 m/s.
Explanation:
Given that,
Frequency = 30.0 kHz
Frequency of echo = 900 Hz
We need to calculate the frequency
Using formula of beat frequency

Put the value into the formula



We need to calculate the speed of the bat
Using Doppler equation

Put the value into the formula







Hence, The speed of the bat is 5.02 m/s.
If you mean pattern designs it’s rocky bumpy and you can see the circle patterns
If you mean phases the here’s a picture
C= 5/9*(F - 32) so F=C*9/5 + 32
F= 25*9/5 +32 = 77 Fahrenheit