Question 1 3 pts 9 1 0 Details A box with a square base and open top must have a volume of 143748 cm". We wish to find the dimensions of the box that minimize the amount of material used. First, find a formula for the surface area of the box in terms of only a, the length of one side of the square base. A(x) Next, find the derivative, A' (x). A'() = The critical value is x = The function is | Select an answer until the critical value, and Select an answer + after, so the critical value corresponds to a local Select an