1. What is the primary problem that comes with using a regular binary search tree for maintaining a search tree with data elements that are inserted and deleted dynamically? What does a 2-3, 2-3-4, or red-black tree do to try to diminish the negative aspect of an ordinary binary search tree?

2. Create a 2-3-4 tree for a total of 15 nodes in the following order of their key values: 1, 2, 3, , 15. Detailed steps for each node are needed. That is, you will need to draw a tree after inserting each and every node. In particular, if any adjustments of the tree (e.g., splitting and combining) are involved, such information will be expected.

3. Create a red-black tree based on the tree you created in Problem 2.