Which of these mappings is a function?

Askate shop rents roller skates as shown on the table below. which graph and function models this situation?

Which zero pair could be added to the function f(x) = x2 + 12x + 6 so that the function can be written in vertex form? o 3, -3o 6,629,-936, 36

Which equation represents a direct linear variationa. y=x2b. y=2/5xc. y=1/xd. y=x+3