Does this graph represent a function? Why or why not?

Given a(-12,5) and b(12,29) find the point that divides the line segment ab three-eighths of the way from a to b

There are three bags: a (contains 2 white and 4 red balls), b (8 white, 4 red) and c (1 white 3 red). you select one ball at random from each bag, observe that exactly two are white, but forget which ball came from which bag. what is the probability that you selected a white ball from bag a?

What is the slope of the line (-7,2) (4,6)