2. (10 points) A group of 20 students have 10 students enrolled in math class, 6 students enrolled in history class and 3 students enrolled in both classes. If a student is randomly selected from the group, what is the probability that the student will be (a) enrolled in either math, history or both? (b) enrolled in math given that also enrolled in history? Define the appropriate events for the above probabilities using uppercase letters like A, B, etc