1. Let A = {3, 4, 5} and B = {5, 6, 7}. Find (a) The union AUB (b) The intersection An B (c) The relative complement of B in A, defined as A \\ B(= An Bc) (d) The symmetric difference AAB = (A \\ B) U(B \\ A). 2. Redefine the following sets of real numbers as intervals on the line, i.e., write them like {x e R : a 2}. (C) C={XER : 15x2 1