a) How many license plates can be made using either two or three letters followed by either two or three digits and contain no letter or digit twice? b) The sixth permutation of the lexicographic permutations of the 24 elements of the set {1, 2, 3, 4} is 1432. Find the next ten permutations in lexicographic order after 1432. c) Suppose that a department contains 10 men and 15 women. How many ways are there to select a committee with six members if it must have At most three women? At least 1 woman and at least 1 man? i. ii.