Consider the following grammar G: S $->$ aSa $|$ bSb $|$ aa$,$ where S is the start

variable and a$,$ b are terminal symbols.

$($a$)[5$ points$]$ Give either a derivation or a parse tree for abaaba.

$($b$)[5$ points$]$ Describe in words the language generated by G$.$

$($c$)[5$ points$]$ Is this grammar ambiguous? No justification is needed.

$($d$)[10$ points$]$ Use the pumping lemma to show that L$($G$)$ is not regular.