Question 7 (12 points) The PX exchange uses maker/taker pricing; orders that add liquidity receive a rebate of $0.001 per share; orders that take liquidity pay $0.002 per share. Sam just entered an order to buy 100 shares limit $20. This order goes into the book. Shortly thereafter Mona enters an order to sell 100 shares, limit $19. a. What is the price paid by Sam net of maker-taker pricing? b. What is the price received by Mona net of maker-taker pricing?