AP EAMCET Medical 2018 Shift 1 Paper

A train moving at 30 ms-1 is blowing a whistle with a frequency 500 Hz. The speed of sound is 345 ms−1. The wind is blowing with a speed 10 ms−1 in the direction of moving train. The apparent wavelengths of the whistle as heard by an observer who is respectivelyin front of and behind the train are