I own a Supercuts barber shop. Up to 12 people an hour want to come get haircuts, which I charge $20 each for. I have 1 cashier that can process 20 people an hour. I have 2 barbers who can process 3 people an hour each (so 6 people an hour total). I pay barbers $16 an hour and cashiers $13 an hour. If I can't change demand, and I can hire as many people as I want, what is my maximum profit per hour?