Ride tickets at the county fair cost $2 each. Let c(n) = 2n represent the total amount spent on riding attractions at the fair as a function of the number of tickets purchased, n.

a. What is the cost of 5 ride tickets?

b. If a person spends $20 on ride tickets, how many tickets did they purchase?

c. : The cost function c(n) is linear.

d. If the fair offers a discount of 25% on ride tickets, what is the new cost function?