Until recently, hamburgers at the city sports arena cost $5.20 each. The food concessionaire sold an average of 4,500 hamburgers on game night. When the price was raised to $5.70, hamburger sales dropped off to an average of 3,250 per night. (a) Assuming a linear demand curve, find the price of a hamburger that will maximize the nightly hamburger revenue. (b) If the concessionaire had fixed costs of $1,500 per night and the variable cost is $0.50 per hamburger, find the price of a hamburger that will maximize the nightly hamburger profit