行走边缘

At the profit-maximizing level of output,marginal revenue and marginal cost are exactly equal.|The process of entry and exit ends only when price and average total cost are driven to equality.In the zero profit equilibrium,economic profit is zero,but accounting profit is positive,so competitive firms stay in business.because firms can enter and exit more easily in the long run than in the short run,the long run supply curve is typically more elastic than the short run supply curve.