Question 3 (6 marks) a) Construct the min-heap by inserting the keys, 6, 9, 4, 3, 2 and 7, one at a time, in that order, to an initially empty heap. Draw the heap after each step. (2 marks) b) The following tree is a (2,4) tree after inserting the keys 12, 25, 2, 32, 65. Draw the resulting (2,4) tree after inserting the key 15. Describe what steps were involved in making the change to the tree's structure. 12 2 25 32 65 (2 marks) c) Out of the following search trees: AVL trees, Splay trees, (2,4) trees, B-Trees and red-black trees, which one would be most appropriate for implementing an Ordered Map that is expected to contain more entries than can be reasonably expected to fit in main memory? Why? (2 marks)