20. Suppose you randomly select two students from the group in Problem 18. What is the probability that:

(a) the first student falls at least 100 SAT-CR points away from the mean (in either direction)?

(b) both students obtain SAT-CR scores above 700?

(c) the first student obtains a score above 650 and the second student obtains a score below 450?

(d) both students fall above 650 or both students fall below 450?

(e) both students obtain scores as extreme as 650?