What are the answers to problems 9 and 10 ?

I'm confused on this could anyone me and show me what i need to do to solve it.

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?

Sweet t saved 20 percent of the total cost of the green-eyed fleas new album let there be fleas on earth. if the regular price is $30 how much did sweet save