MATH 251 WEEK 5 RECITATION SPRING 2022 3 (6) We want to construct a box whose base length is twice the width. The material used for the top and bottom of the box is ten dollars per square foot and the cost of the material used for the sides is eight dollars per square foot. If the box must have a volume of 60 cubic feet, determine the dimensions that will minimize the cost of the box. (7) Find the derivatives of the function f(x) = vi(a?-2x) T-Ar+5