12. A firm will operate at that output at which MC = MR (LO1, 6) a) only in the short run b) only in the long run c) in both the short run and the long run d) in neither the short run nor the long run 13. At an output of 5, MC = $49 and ATC = $52. At an output of 6, MC = $59 and ATC = $53. At the break- even point, ATC is (LO6) a) above $53 b) $53 c) between $52 and $53 d) $52 e) less than $52 14. Statement 1: The firm's short-run supply curve runs up the marginal cost curve from the shut-down point to the break-even point. Statement 2: The firm will not accept a price below the break-even point in the short run. (LO6) a) Statement 1 is true, and statement 2 is false. b) Statement 2 is true, and statement 1 is false. c) Both statements are true. d) Both statements are false