IV. Indexing 1) Describe the advantages and differences of B+-tree over B-tree. 2) What are the differences between primary, secondary, and clustering indexes? V. Query Optimization Consider the following relations: Branch (BranchName, Assets, City) Customer (CustomerName, Address, City). Account (Account Number, BranchName, CustomerName, Balance). The following query finds the assets and names of all banks that have depositors living in Blacksburg and have a balance of more than $100,000: isset, Branchliane (Customer City="Blacksburg' AD Balance>100.000 (Customer Account Da Branch) Use the heuristic rules to rewrite this query into something that be executed much faster. (Hint: You may draw the query tree and optimize it step-by-step as shown in the textbook)