Problem 1 Find (1) an NFA and (2) a regular expression for the following languages on (a, b L = {w : na(w)-na(w) (mod 3)-0). . L = {w : 2'4(w) +3ms(w) is even). Note: na(w) means the number of a's in the string w, and n is defined in the same way. Problem2 (1) Find a DFA for the language L = {a"V" : n + m is odd). (2) Then find n regular gramnar for the language L Problem 3 Define nor operation for the language as follows Show that the family of regular languages is closed under the nor operation