Which of the relations given by the following sets of ordered pairs is not a function? A. {(-6,4), (- 3, – 2), (0,5), (1, - 2), (2,3)}
B. {(-4, - 2), (-1, - 1), (-1, 1), (3,5), (7, 10)}
C. {(-8,3). ( - 6,5), (- 4,2), (-2,7), (- 1,4)}
D. {(5.0), (4,0). (3.0), (2.0), (1.0)}

Barrett is comparing the membership fees for two museums. the art museum charges a one-time fee of $8.25 plus $2.25 per month. the science museum charges a one-time fee of $10.75 plus $3.50 per month. how much does barrett save by joining the art museum instead of the science museum?