1. (12 p.) Give a BNF grammar for each of the languages below: (a) The set of all strings consisting of one or more a's (b) The set of all strings consisting of zero or more a's, with a comma between each a and the next. There should be no comma before the first or after the last a. (c) The set of all strings consisting of zero or more digits. (d) The set of all strings consisting of one or more digits separated by commas. There should be no comma before the first or after the last digit. (e) The set of all strings consisting of keyword begin followed by one or more statements with a semicolon after each one, followed be the keyword end. Use the non-terminal statement for statements and do not give productions for it. (f) The set of all strings consisting of an open bracket (the symbol [ ) followed by a list of one or more digits separated by commas., followed by a closing bracket (the symbol ] ). There should be no comma before the first or after the last digit