Casey runs a business that makes custom-printed hat. It will cost him $7 each to purchase and print on hat, and he will have to pay a rent of $1,600 per month for him workshop. Based on market research, Casey estimates that he can sell custom hat for $23 each. a) Calculate the number of hat he needs to sell per month to break-even. hat b) Calculate the break-even in dollars (round off to the nearest cent).