please help me get started on this question
An urn contains 3 Red and 4 White marbles. A fair coin is flipped. If the flip is Heads then 1 Red and 2 White marbles are added to the urn. On the other hand, if the flip is Tails, then 1 Red and 2 White marbles are removed from the urn. Two random marbles are now drawn from the urn without replacement. (i) What is the probability that both of the drawn marbles are White? (ii) What is the probability that the flip was Heads, given that the two drawn marbles have different colors?