Write a set of BNF grammar rules that will parse a programming language that can have variable type declarations such where the variable has name and a type which can be either integer or boolean, and optionally has a constant default value:E.g.var i : integer;var j : integer = 6;var b : boolean;var b2 : boolean = true;var b3 : boolean = false;2.Show an example of why the following grammar is Ambiguous.