Which description of the transformation of z on the complex plane gives the product of z=sqrt2(cos(pi/4)+isin(pi/4)) and w=sqrt8(cos(pi/4)+isin(pi/4))?

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?