(10%) Problem 9: You are standing on a train station platform as a train goes by close to you. As the train approaches, you hear the whistle sound at a frequency of f1 = 99 Hz. As the train recedes, you hear the whistle sound at a frequency of f2 = 74 Hz. Take the speed of sound in air to be v = 340 m/s. Randomized Variables f1 = 99 Hz f2 = 74 Hz 5 25% Part (a) Find an equation for the speed of the sound source vs, in this case it is the speed of the train. Express your answer in terms of f 1, f2, and v. 25% Part (b) Find the numeric value, in meters per second, for the speed of the train. A 25% Part (c) Find an equation for the frequency of the train whistlefs ("s" is for "source") that you would hear if the train were not moving. Express your answer in terms of f1, f2, and v. D A 25% Part (d) Find the numeric value, in hertz, for the frequency of the train whistle f5 that you would hear if the train were not moving. Grade Summary f: = I Deductions 0% Durant: n1 1 m 0L