1. Let U (1, 2, 4, 5, a, b, c, d, e) and Q = (2, 4, b, d).
   Use the roster method to write the complement of set Q.
   4. Let U= {21, 22, 23, ..., 40]) and A = (21, 22, 23, 24, 25).
   Use the roster method to write the complement of set A.