2. Define an operation on the set R by a*b = a + 3b for all a, b R. * (a). Show that is not associative. (b). Show that there is no identity element for *. (l.e., show that there is no c ER such that is an identity element for *.) 3. Let X and Y be sets, and let f: X Y be a map. Define a binary relation = on X by declaring that