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What is the frequency, wavelength, and speed of sound from the observer

A train, standing in a station-yard blows a whistle of frequency 400 Hz in still air. The wind starts blowing in the direction from the yard to the station at a speed of 10 m/s. What is the frequency, wavelength, and speed of sound from an observer standing on the station's platform? Is the situation exactly identical to the case when the air is still and the observer runs towards the yard at a speed of 10 m/s? The speed of sound in still air can be taken as 340 m/s.