Which of the following graphs represent a function?

The vet charges $45 for an office visit and $10 for each vaccination your dog needs. write an eaquation

The larger of two number is 4 less than twice the smaller number. the sum is 41. find the numbers

It took alice 5 5/6 hours to drive to her grandparents' house for . on the way home, she ran into traffic and it took her 7 3/8 hours. how much longer did the return trip take? write your answer as a proper fraction or mixed number in simplest form. the trip home took __hours longer. ?