Question $2$: Write CFGs for the following language descriptions in normalized form.

$L=a^n{b}^{3n}$;$n>0.$

$L=a^{n+1}{b}^{n+3}$;$n0$

Question $3$: Using the second version of Pumping lemma to prove that the given language is not context free.

$L=ww$; w belongs to $(a+b{)}^{*}$