Find a counterexample to show that the following statement is false. for all sets a and b, (a ∪ b)c = ac ∪ bc. assume that all sets are subsets of a universal set u = {1, 2, 3, 4, 5}. (enter your answer as a comma-separated list in the form a, b where both a and b are written in set-roster notation. enter empty or ∅ for the empty set.)