Exercise 4.1.1: Prove that the following are not regular languages a) (0"1n|n 2 1). This language, consisting of a string of 0's followed by an cqual-length string of 1's, is the language Loi we considered informally at the beginning of the scction. Here, you should apply the pumping lemma in the proof. b) The set of strings of balanced parentheses. These are the strings of char- acters "(" and " that can appear in a well-formed arithmetic expression *c) O"IO" n 21) d) (0"]"2" | n and n are arbitrary integers)