The question asks you to give an reguler (left-most or right-most grammer) instead of giving a context free grammer!!! If you cannot give an reguler grammer, then using pummping lemma proves it.

For each of the following languages, give a regular grammar if it is regular Otherwise, prove that it is not regular (1). L1 bab: n, k 20) (2). L2 a: n is a prime number) (3). L3 fw: wE {a, b* and w w) (4) L4 fua2bv: u,v E fa, bl*, uv e L, and L is any regular language\