The cost, in dollars, of a one-day car rental is given by C(x) = 31 + 0.18x, where x is the number of miles driven. In this function,
A$0.18 is the cost per day to rent the car and $31 is the cost per mile.
B$31 is the cost per day to rent the car and $0.18 is the cost per mile.
C$18 is the cost per day to rent the car and $0.31 is the cost per mile.
D$31 is the cost per day to rent the car and $18 is the extra cost for unlimited miles.
A$0.18 is the cost per day to rent the car and $31 is the cost per mile.
B$31 is the cost per day to rent the car and $0.18 is the cost per mile.
C$18 is the cost per day to rent the car and $0.31 is the cost per mile.
D$31 is the cost per day to rent the car and $18 is the extra cost for unlimited miles.