A train pulls out of a station at a speed of 35 km/hr. The train's horn emits sound at 281 Hz. The speed of sound in air is 326 m/s. (a) What is the frequency heard by a traveller waiting at the station? Number Hz (b) A second train approaches the station, travelling in the opposite direction. It travels at 35 km/hr, while blaring its horn at 281 Hz. What is the frequency heard by the traveller at the station? Number Hz (c) If both trains blare their horns simultaneously, what is the dominant frequency heard by the traveller? Number Hz The traveller at the station mimics train horns by blowing a whistle at 234 Hz. (d) A passenger inside the first train hears the sound of the whistle. What is the frequency perceived by the passenger? Number Hz (e) A passenger inside the second train hears the sound of the whistle. What is the frequency perceived by the passenger? Number Hz