In the first part, what might be examples of short-run fixed and variable costs? What role do diminishing marginal return affect short-run productivity and costs for the company? Amazon did try having retail stores, but I believe they have closed them. What aspects of Amazon online operations allow it to achieve large economies of scale? How is it able to maintain it position? How has Apple dealt with diseconomies of scale? What actions has it/should it take to lower its cost per unit