A school council is planning a battle of the bands. They expect that 700 tickets will be sold if the ticket price is $5. A survey shows that if the ticket price is raised by $0.50, 50 fewer tickets will be sold. The situation can be modelled by y = -25p^2 + 100p + 3500, where y represents the revenue from ticket sales in dollars and p represents the number of times the ticket price is increased by $0.50.What is the maximum revenue the student council can make?