Answer:
90degrees I'm pretty sure
The source of the sound it moving closer to you because the wavelength is shortened. The shorter the wavelength, the higher the frequency, the higher the pitch
It would take 5.0 s for a racehorse to accelerate from rest to a speed of 15 m/s with an acceleration of 3.0 m/s.
Take 15 / 3.0 to get your answer of D. 5.0 s
Hope that helps u out!
And the other answer is jeje