A ferry carries people across to an island airport. It carries 2480 people per day at a cost of $3.70 per person. Surveys have indicated that for every $0.05 decrease in the fare, 80 more people will use the ferry. Use x to represent the number of decreases in the fare.

a) What expression models the fare per person.

b) What expression models the number of people that would use the ferry per day.

c) Determine the expression that would model the revenue, R, for the ferry, which is the product of the number of people using the ferry per day and the fare per person.

d) Use completing the square to determine the vertex of the revenue function.

e) Use the information in the vertex to determine the maximum revenue, number of people using the ferry per day, and the fare per person.