Refer to Exercise 5.88 but now suppose the sampling is done in two stages: First a list is selected at random and then, from that list, two persons are selected at random without replacement. Let Y denote the number of females in the sample.
(a) List the elementary outcomes concerning the possible selections of this and the possible compositions of the sample
(b) Determine the probability distribution of Y.

Data from in Exercise 5.88 

A large science department at the university made a list of its top 20 juniors and 25 seniors. The first list contains 7 females and the second 10 females. One person is randomly selected from each list and the two selections are independent. Let X denote the number of females selected .