Because it is releasing heat from your body sweating and prespirating rlmelease heat so that you body will cool
I'm a little confused by your question.
If you mean what is popular sovereignty, it is the belief that the governments is made and sustained by the consent of the people that it governs.
V: velocity of wave
f: frequency
L: wavelenght
v = fL => L = v/f => L = (3x10^8)/(900x10^3) => L = 3.33 x 10^2m