3. A set of widgets contains 9 black and 11 red widgets. We must randomly select 5 widgets from the set. What is the probability that we select exactly 2 black and 3 red widgets? 4. An urn of marbles contains 15 blue and 21 yellow marbles. We must randomly select 12 marbles from the urn. What is the probability that we select exactly 5 blue and 7 yellow marbles