I need help on C and D using a graphing calculator and how to get to the final answer:

X 9. An open tank with a square base and vertical sides is to have a capacity of 32 f+3. Find the dimensions of the tank that will minimize the cost of lining the tank with copper ( surface area plus the base. Let x = the length of a side of the base and y = the height V= X 2 y a. Write an equation for the volume in terms of x and y and the given volume. b. Solve part a for y and use this expression to write the surface area function ( the base and 4 sides of the tank) in terms of x. SA = X2+ 4XY (plug my) c. What dimensions of the tank will minimize the surface area? d. What is the minimum surface area? Assume the rectangle has dimensions