cayetanoburneo cayetanoburneo 19-04-2020 Physics contestada A plane flies at 200 m/s, emitting a 600 Hz roar. Assuming a 340 m/s speed of sound, what will be the frequency of sound waves heard by a stationary observer directly behind the plane? I NEED THIS ASAP PLEASE A. 247 Hz B. 260 Hz C. 378 Hz D. 400 Hz