(4) A rectangular beam is cut from a cylindrical log of radius 5in. The strength of a beam of width w and height h is proportional to wh. Find the width and height of the beam of maximum strength. h 5n (5) Let h(x) - +kx, where k is a constant. For what value(s) of k does h have (a) No critical points? (b) One critical point? (6) Find a function of the form f(x) = ax + b/x has a local minimum value 12 at x = 3 and a local maximum value -12 at x = -3. [You have to find the values for a and b.]