Problem 1. In class, we have seen that if A and B are regular languages over an alphabet E, then so is the language AUB. Which of the following languages are guaranteed to be regular as well? Prove that your answer is correct. A=I* \A= {w E * : w A}; An B = {w * : WE A and w E B}; A B = {W EI* : W E A but w B}; and A B = {W * : w is in exactly one of A and B}