2. Find CFGs for these languages: (i) All words of the form a'b'a, where x, y, z= 1 2 3 . . . and x + z = y = {abba aabbba abbbaa aabbbbaa...) Hint: Concatenate a word of the form a"b" with a word of the form bam. (ii) All words of the form a'b'a, where x, y, z= 1 2 3 . . . and y = 2x + 2z = (abbbba abbbbbbaa aabbbbbba . . .) (iii) All words of the form aba, 3. where x, y, z= 1 2 3 . . . and y = 2x + 2z = (abbba abbbbaa aabbbbba (iv) All words of the form a*b'a-b", where x, y, z, w = 1 2 3 . . . and yx and z>w and Hint: Think of these words as x + z = y + w (a'b')(b'a')(a'b')