Astudent standing in a canyon yells "echo", and her voice produces a sound wave of frequency of f = 0.61 khz. the echo takes t = 3.9 s to return to the student. assume the speed of sound through the atmosphere at this location is v = 322 m/s.

 is the distance from the obstacle of reflection.

wavelength

Explanation:

Given that:

We know,

During an echo the sound travels the same distance back and forth.

 is the distance from the obstacle of reflection.

Now the wavelength of sound waves:

answer: point c: b. 1/2 potential, 1/2 kinetic, point a: 3/4 of its potential energy, point d or b: 3/4 potential, 1/4 kinetic

explanation: i cant explain. it's difficult to explain.

so easy. just google the electromagnetic waves and it’ll pop up.