It costs $4.50 per person for 2 people and $3.00 per person for 3 people to go on a horse carriage ride. using c to represent the cost per person and n to represent the number of people, which equation models this relationship? a. c + n = 7.50 b. 2n + 3n = 7.50 c. cn = 9.00 d. 9.00n = c