Suppose the book-printing industry is competitive and begins in a long-run equilibrium. Then Hi-Tech Printing Company invents a new process that sharply reduces the cost of printing books. The following graph shows Hi-Tech's initial marginal-cost curve (MC1) and average-total-cost curve (ATC1 ) before the new technology, and its marginal-cost curve (MC2 ) and average-total-cost curve (ATC2 ) after the new technology. ATC1 P ATC 2 Price of Books P2 MC 2 Quantity of BooksNow suppose the patent expires and other firms are free to use the technology. Which of the following statements are true about what happens in the long run? Check all that apply. All firms earn zero profit. The market price falls to P2. All firms' average-total-cost curves decline to ATC