Ruby bought an animal bank for her nephew. She is the only one who puts money in the bank, and no money is taken out. The function f (v) = 10 + 2v describes the amount in the bank after v visits with her nephew. Which statement is true?
a) Ruby puts $2 in the bank each visit.
b) Ruby puts $10 in the bank each visit.
c) There was $2 in the bank before the first visit.
d) There was $12 in the bank before the first visit.