Which statements describe a function that is nonlinear? Select each description of a nonlinear function.
A) given the total amount spent, x dollars, the total amount of change received after paying at the grocery store with $80
given the number of hours worked, x, the total amount of money earned when paid $15 per hour
B) the perimeter of a rectangle, given that the width is half the length and the width is w meters
C) the volume of a cube, given the side length of the cube is x centimeters
D) the area of a circle, given the radius is r inches