Evan buys a new car that costs $23,740. Anna buys the same new car, only she buys the hybrid model. Anna’s hybrid car costs $31,140. Anna pre-pays for gasoline so that the cost for her gasoline will always be $2.40 per gallon forever. Using the graph, which represents a combined city and highway driving annual fuel usage, write an equation that represents the exact cost for any amount of miles she drives. Be sure to define the variables you are using for your equation.