A train is moving parallel and adjacent to a highway with a constant speed of 23 m/s. A car is traveling in the same direction as the train at 46 m/s. The car’s horn sounds at 550 Hz and the train’s whistle sounds at 360 Hz. When the car is behind the train what fre- quency does an occupant of the car observe for the train whistle? The speed of sound is 343 m/s. Answer in units of Hz