Which language is accepted by the following automata?

III.

a$)$ Convert the following regular expression to NFA:

$(aab{)}^{**}a(ba{)}^{**}$

b$)$ Show that the below PDA accept the word: abbbcccc

c$)$ Convert to Chomsky normal form the following grammar, show all the steps:

$SMN$

$M$abb$|aMb|$

$Nc|cN|$