Mr. Smyth uses the function L(x)=2x^2 to determine the length, in feet, of his landscaping projects. He uses the function W(x)=5x−2 to determine the width, in feet, of each project. Which function could Mr. Smyth use to determine the price, P(x) , for a rectangular project if he charges $20 per square foot? A. P(x)=10x^2−4x
B. P(x)=2x^2+5x−2
C. P(x)=200x^3−80x^2
D. P(x)=40x^2+100x−40