Implement the static method declared as follows:

/**

* Divides {@code n} by 2.

*

* @param n

* {@code NaturalNumber} to be divided

* @updates n

* @ensures 2 * n <= #n < 2 * (n + 1)

*/

private static void divideBy2(NaturalNumber n) {...}

Implement the static method declared as follows:

/**

* Checks whether a {@code String} is a palindrome.

*

* @param s

* {@code String} to be checked

* @return true if {@code s} is a palindrome, false otherwise

* @ensures isPalindrome = (s = rev(s))

*/

private static boolean isPalindrome(String s) {...}