+244 A police car (a.k.a: the fuzz) has an 820-Hz siren blaring and the red/blue lights flashing as he chases a rougue physics professor. He is traveling at constant speed of 45.0 m/s on a day when the speed of sound through air is 343 m/s. A hitchiker watches the police car approaches, pass, and receede. What change of frequency does the hitchhiker hear?
A.116 Hz
B.724 HZ
C.0 Hz
D.219 Hz
