There are many square prisms with volume 125in³. Let w represent the side length of the square base and h represent the height in inches. Then the formula for the volume V, in cubic inches, of these prisms is V = w²h, and the equation for the surface area S, in square inches, is S = 2w² + 4wh. Write an equation for S as a function of w when the volume of the prism is 125 in³.
a) S = 2w² + 4wh
b) S = w² + 4wh
c) S = 4w² + 2wh
d) S = 2w² - 4wh