this is data structure and please java to solve thank you

3 Linked List The following exercises deal with coding a LinkedList. The LinkedList is composed of generic Node objects. The LinkedList contains a Node head referencing the first node in the list. The LinkedList contains a Node tail referencing the last node in the list. The LinkedList contains a method size() that returns the number of elements in the list. The Node objects are doubly-linked, and contain public variables next and prev, which reference the next and previous nodes in the list respectively. 12. (3 points) Write a method called deleteList(), which removes all the items in a list, making it empty. // again, this is an instance method inside LinkedList // so you have access to head, tail (optional), and the Node class public void deleteList() { 13. (10 points) Write an instance method called count. Count iterates over a LinkedList and returns the number of times item occurs in the list. // This is an instance method, so you can access the head, tail, and the Node class public int count(E item) { 14. (2 points) What is the time complexity of this algorithm