Respuesta :
This is called the Doppler effect. It's essentially a compression of the sound wave. When the sound wave compresses, the wavelength is therefore decreased. Becasue frequency is inversely related to the wavelength, the frequency is changed as well.
F = v/λ
F - frequency
v - velocity
λ - wavelength
F = v/λ
F - frequency
v - velocity
λ - wavelength

Answer:
D) pitch and frequency
Step-by-step explanation:
If it's USATestprep it's D I just answered this one.