a) Explain the difference between explicit and implicit costs of production. b) Explain the reasoning behind the U-shaped, long-run, average cost curve. c) Explain the law of diminishing marginal returns. d) Describe economies and diseconomies of scale. e) Given the following data, calculate the total fixed, total variable, and marginal costs at each level of production. Quantity Total Cost Total Fixed Total Variable Average Marginal Cost Cost Total Cost Cost 0 $100 1 $20 2 $30 3 $100 4 $75