The New Kilkenny Highway Commission is installing a camera-based highway monitoring system to track the license plate numbers of cars entering and leaving the highway. They are examining two different camera systems. System A can track three cars per second, takes up 1 foot of space on the overhead beams, and costs $4,500. System B can track 13 cars per second, takes up 5 feet of space on the overhead beams, and costs $32,000. The highway commission cannot spend more than $85,000 for the system, and has 25 feet of overhead beam space available. They also can only install a maximum of nine devices due to wiring restrictions. Formulate a linear programming model to maximize the number of cars the system can track. List the extreme points and determine the solution graphically.