On which interval does h(t) have an average rate of change of zero? A)-10<= t<= -5
B)5<= t<= 10
C)0<= t<= 5
D)-5<= t<= 0
HELP PLEASE! I do not understand

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?