EXERCISE 11 Give a grammar for each of the following languages. You need not state it formally; just list the productions, and use S as the start symbol. a. The set of all strings consisting of zero or more as with a b after each one. b. The set of all strings consisting of one or more as with a b after each one. c. The set of all strings consisting of one or more as, with a b between each a and the next. (There should be no b before the first or after the last a.) next. (There should be no b before the first or after the last a.) list of zero or more digits separated by commas, followed by a closing bracket (the d. The set of all strings consisting of zero or more as, with a b between each a and d e. The set of all strings consisting of an open bracket (the symbol D followed by a symbol ). (A digit is one of the characters 0 through 9.)