Question: A student standing in a canyon yells "echo," and her voice produces a sound wave of frequency of f = 0.56 kHz. The echo takes t = 3.5s to return to the student. Assume the speed of sound through the atmosphere at this location is v = 331m/s. Input an expression for the distance,d, the canyon wall is from the student. How many wavelengths are between the student and the wall?