A firm is producing 20 units with an average total cost of $25 and a marginal cost of $15. If it increases production to 21 units, which of the following must occur?
选项:
A: Marginal cost will decrease.
B: Marginal cost will increase.
C: Average total cost will decrease.
D: Average total cost will increase.
发布时间:2024-04-14 22:15:47