Answer in 5 minutes

D Question 15 1 pts A fire truck emits its siren at 800 Hz. As the truck approaches a stationary observer on the sidewalk, he perceives the pitch to be 920Hz. Approximately what pitch does he hear after the truck passes and is moving away? Assume the truck's velocity remains constant, and that the velocity of sound in air is 340m/s. O 757 Hz O 780 Hz 708 Hz O 695 Hz