The amphitheater has two types of

tickets available, reserved seats and

lawn seats. the maximum capacity of

the venue is 20,000 people, however,

they must sell at least 5,000 tickets for a

concert to be held. as an additional

constraint, the number of lawn seats

cannot exceed the number of reserved

seats. if reserved seats profit $65 each

and lawn tickets profit $40 each, how

many of each must they sell to

maximize their profits?