1. How can you implement a queue data structure using a doubly linked list? Do you think it is necessary to use a doubly linked list rather than a singly linked list or not?
2. If we need a add and delete function that can work on any position in a list, should we use the array implementation or the linked list implementation? Explain the complexity of these operations for each of the implementations.
3. Please illustrate the process of inserting 2, 10, 9, 4, 6, 8, 5, 3, 7 to an initially empty binary search tree.