Answer the following questions:

a$)$ Give an example of a string of length $6$ containing ab that is accepted by the FSA shown in figure $1.$

$[2$ marks$]$

b$)$ Give an example of a string of length $5$ that is rejected by the FSA shown in figure $1.$

$[2$ marks$]$

c$)$ Describe the language of this automaton in terms of a Regular Expression.

$[3$ marks$]$