Design a state diagram to recognize variable names in a new language such that a variable name starts with any one of the % or @or $ or _ characters, then followed by at least one letter, then followed by any combination of letters and digits. Both lowercase and uppercase letters can be used. As examples; while a and @x1xz are valid variable names; $1 and a2bc23xYz are not valid variable names. After that, write BNF or EBNF rules by using your state diagram to generate the valid variable names in the new language. Show that your rules can generate a valid variable name by applying a leftmost derivation.