Which of the following pairs of sets are disjoint?
Write all the proper subsets of the set A = {1, 3, 5}.
         Â
{1}, {3}, {1, 3}, {1, 5}
Which  of the following sets are comparable?
A = {a, Â b, c}, B = {b, c, d}, C = {b, c, d, e}, D = {a, b, c, ,e}
A = { a, i, o}, B = { e , o, i}, C = {i, ,e, o, u}, D =Â Â Write a suitable universal set for A, B, C, and D.