Please explaind your process and solve the questions Design finite automata that accept the described languages by drawing state diagrams.

$(10$pts$)$ The set of strings over $\{a,b\}$ in which the number of a$\text{'}$s is divisible by three.

$(10$pts$)$ The set of strings over $\{a,b\}$ that do not contain the substring aaa.

$($Hint: design a finite automaton to accept the complement of the language. Then interchange

the accepting and non$-$accepting states.$)$