Is the following relation a function? yes or no

Two parallel lines are crossed by a transversal.what is value of x

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

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. how many hours after the truck's departure will the two meet?