A company in a purely competitive industry is currently producing 1000 units a day at a total cost of $450. If the firm produced 800 units per day, its total cost would be $300, and if it produced 500 units per day,its total cost would be $275. What are the firms average total cost per unit a these levels of productions? If every firm in this industry has the same cost structure, it the industry in long-run competitive equilibrium?