Consider the grammar g = (v, t, e, p) for expressions (e for short) such that v = {e, a,+,*}, t = {a,+,*}, e is the starting symbol, and

p = {e -> (e) | e + e | e * e | a}.

a) explain whether g is regular, context-free, or context-sensitive, respectively. explain why or why not.
b) explain the language l(g) that is generated by g, especially, what kind of strings belong to the language. be specific. also, give six shortest strings that belong to l(g).
c) show that (a+a)*(a*(a+a)) belongs to l(g) by showing that it is derivable from e. show every step of derivation.