Answer: $56
Explanation:
The profit-maximising quantity for a perfectly competitive firm is the point where Marginal Cost equals Marginal Revenue.
For a perfectly competitive firm, the Horizontal line is the Price, the Marginal Revenue and the Demand curve.
The point where Marginal cost equals Marginal revenue is at 4 bushels.
The Average total cost at 4 bushels is $14 so the total cost is;
= 14 * 4
= $56
