Assume the price of silk ties in a perfectly competitive market is $21 and that the typical firm confronts the following costs: Quantity (ties per day) 0 Total Cost $10 17 23456009 26 37 50 65 82 7 101 8 122 145 10 170 4 Instructions: Enter your responses as a whole number a. What is the profit-maximizing rate of output for the firm? (Hint: Use the profit-maximizing rule.) ties per day Instructions: Enter your responses as a whole number. a. What is the profit-maximizing rate of output for the firm? (Hint: Use the profit-maximizing rule.) ties per day b. How much profit does the firm earn at that rate of output? $ c. If the price of ties fell to $11, how many ties should the firm produce? ties per day d. At what price should the firm shut down? (Click to select)