d. Indeterminate without information about revenue 18 A firm is producing at its minimum average total cost in the short run. What effect will a small reduction in output have on the firm's marginal cost (MC) and average total cost (ATC)? a. Both MC and ATC fall b. MC falls while ATC rises c. MC rises while ATC falls d. Both MC and ATC rise - 19 Which of the following statements represents a difference between short run and long run