11. We want to construct a box whose base length is 3 times the base width. The material used to build the top and bottom cost $10 per m2 and the material used to build the sides cost $6 per m². o 1 – 3 (a) If the box must have a volume of 50 m3, find an expression for the height h in terms of w. [1 mark] 800 dollars. (b) Hence show that the total cost C(w) to build the box is given by C(w) = (60w? +