长期平均成本曲线是怎么样得到的？
向上倾斜的CC曲线表示厂商数量越多，平均成本越多，各厂商销量越低。交点处为行业的均衡厂商数。
If the number of firms increases, each firm will sell less, so firms will not be able to move as far down their average cost curve.
绘出一家典型企业的边际成本和平均总成本曲线。解释其形状和交点。
Draw the marginal-cost and average-total-cost curves for a typical firm. Explain why the curves have the shapes that they do and why they cross where they do.
应用推荐