Consider the following code:

$1$ public class Age $\{$

$2$ private int age;

$3$

$4$ public $?$ int square$($int $n)\{$

$5$ return $n**n$;

$6$

$7$

$8$ public $?$ int getAge$()\{$

$9$ return age;

$10$

$11\}$

In which method header should you add the static keyword?

square$($int n$)$ header

getAge$()$ header