4. A video club costs $20 to join. Each video that is rented costs $2.25. Let v represent the number of videos. Identify the independent and dependent variables. Then, write a rule in function notation for the situation.
a. Independent: videos rented; Dependent: total cost; f(v) = 2.25v - 20
b. Independent: videos rented; Dependent: total cost; f(v) = 2.25y + 20
c. Independent: videos rented; Dependent: total cost; f(v) = 20v +2.25
d. Independent: total cost; Dependent: videos rented; f(v) = 20v – 2.25