A student standing in a canyon yells "echo", and her voice produces a sound wave of frequency of f $=0\mathrm{.}73$ kHz$.$ The echo takes t $=3\mathrm{.}9$ s to return to the student. Assume the speed of sound through the atmosphere at this location is v $=326$ m$/$s$.$

$$ Part $($a$)$

What is the wavelength of the sound wave in meters?

$$ Part $($b$)$

Input an expression for the distance, d$,$ the canyon wall is from the student.

$$ Part $($c$)$

How many wavelengths are between the student and the wall?