Which relation is not a function?

Helpo due now

If f(x)= 3x+6 which of the following is the inverse of f(x)

Inez has a phone card. the graph shows the number of minutes that remain on her phone card a certain number of days.

Fa bus driver leaves her first stop by 7: 00 a.m., her route will take less than 37 minutes. if she leaves after 7: 00 a.m., she estimates that the same route will take no less than 42 minutes. which inequality represents the time it takes to drive the route, r?