Calvin babysits for $6 an hour. Marilyn charges $10 plus $3 an hour. After how many hours is it cheaper to hire Marilyn?

What is the order of magnitude for the number of liters in a large bottle of soda served at a party

Triangle xyz has vertices x(1,3), y(0,0)

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?