Select all the relations that represent a function. a.(2,3) (4,3) (6, 2) (5,7)
b.(2,3) (4,9) (6, 2) (5,7)
c.(5,4) (5, 7) (2,7) (3,5)
d..(4,8) (7,5) (8,4) (5,7)

Einstein office equipment has a rental plan for office machines. a fax machine that lists for $722.98 can be rented for 22% of the price annually. the state imposes a usage charge of 3.2%. if stephen hawking travel decides to rent the fax machine, what will its total monthly rental charge be?