QUESTION 23 A max-heap structure has which property? Unlike normal binary trees, heaps can never be used to implement priority systems. Every node stores a value that is greater than or equal to the value of either of its children. Every node stores a value that is less than or equal to that of its children. Heaps are, by definition, never complete binary trees. QUESTION 24 In a heap data type, a siftdown operation ..... is an algorithm that re-orders elements of a tree into a heap. It assumes that the two subtrees are already heaps. is a linearly recursive algorithm that ensures that the lowest values in the heap are in internal nodes is a strictly iterative algorithm that reorders heaps into binary search trees. tends to move minimum values into internal nodes. QUESTION 25 In a simple binary search tree, what happens if we input values in order? The tree becomes unbalanced, and is no better at search than a linked list. The tree will be full. The tree will be complete