The tree diagram below depicts a heap being used to implement a priority queue. The numeric values seen in the diagram are the priority values. Enqueue an item with a priority value of 21 , then execute a dequeue. After those two operations have been completed, what does the underlying array look like? List the elements in the resulting heap in the order in which they appear in the array, from left to right, i.e., from index value 0 to the largest index value