An ambulance travels down the highway at a speed of 128 km/h. Its siren emits a sound at a frequency of 925 Hz. A car traveling at 75 km/h is on the other side of the highway (it is moving in the opposite direction). The speed of sound in air is 343 m/s. (A) What is the frequency of the siren heard by a passenger in the car as the car and ambulance approach each other? (B) What is the frequency of the siren heard by a passenger in the car as the car and ambulance move away from each other?