Problem 2 (5 points). Let ALLDFA-{(A): A is a DFA and L(A) = *). Show that ALLDFA is decidable. Problem 3 (5 points). Let SUBSETDFA-A, B L(B)). Show that SUBSETDFA is decidable. A and B are DFAs and L(A) C Problem 4 (5 points). A prunable state in a DFA is some state that is never entered while processing any input string. Show that the following language is decidable: SIMPDFA-[A) : A is a DFA with no prunable states)