4- a) A person has 4 pairs of colored socks, where each pair is of a different color and the socks are all mixed up in a drawer. If that person is pulling socks out of the drawer in the dark (cannot see), how many socks must she/he pull out to ensure they have a pair of the same color?

b) If set A = {1, 2, 3, 4} list all of the possible subsets.

c) How many ways can you arrange the letters of the word Antithesis: