完全竞争

问题如下：

QuestionWhen a perfectly competitive firm reaches a long-run equilibrium, which of the following best describes its supply curve?

选项：

A.marginal cost schedule.

B.average revenue schedule.

C.marginal revenue schedule.

解释：

1. True. The supply curve for a perfectly competitive firm in the long run is best described by its long-term marginal cost curve. This is because, in equilibrium, the firm determines its output where MR equals MC.
2. False. The horizontal line that represents the firm's price level is its long-term average revenue curve.
3. False. For perfectly competitive firms, their demand curve coincides with both their marginal revenue and average revenue curves. Given its operational costs, the main decision the firm makes is its production quantity. This is determined where MR equals MC, with the demand curve being perfectly elastic. Nonetheless, the firm consistently seeks ways to reduce its long-term costs.

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