5. Consider the following linked list LinkedList Node Node Node Node first 12 last and the following code for a linked list and its nodes: public class LinkedList f Node first; Node last; public class Node [ String item; Node next; public Node (String item, Node next) f this.itemitem; this. next next ; (a) Write a method in LinkedList with the signature public void addBeforeLast (String item) that adds the provided item before the last element. For example, calling addBeforeLast("10") on the above linkedlist should insert 10 between 12 and -1. Your method should handle the cases of being called with an empty list, with a list with only one element, and all other cases. public void addBeforeLast(String item)