Firms in a perfectly competitive industry make zero economic profit in the long runbecause for a perfectly competitive industry there are no barriers to entry so itsrelatively easy to enter or exit the market. Therefore, it easy for firms to earn aneconomic profit in the short run; if a profit is being made in the short run, newbusinesses will enter in the long run, likewise, if firms are losing money in the shortrun they'll exit the industry in the long run. Hence, in the long run, the economicprofit returns to zero and the market equilibrium price is where the price, thelong-run average cost, marginal cost, and short-run average total cost are all equal.Here the economic profit is zero, and the firm breaks even, leaving no incentive forother firms to enter the industry