Mabel's Fables is a firm that produces children's books according to production function Q = 3K0.75L0.25, where K is capital and L is labour. Wages cost $1 and renting capital costs $3. (a) Find the long-run total cost function. Does the cost function show economies of scale, diseconomies of scale, or constant economies of scale (no explanations needed)? (b) In the short run, the amount of capital is fixed at 5 units. Find the short-run total cost function. Does it show economies of scale, diseconomies of scale, or constant economies of scale?