8-43. Consider the following two relations for a firm: EMPLOYEE(Employeeld, EmployeeName, Contact, Email) PERFORMANCE(Employeeld, DepartmentID, Rank) The following is a typical query against these relations: SELECT Employee_T.Employeeld, EmployeeName, DepartmentID, Grade FROM Employee_T, Performance_T WHERE Employee_T.Employeeld = Performance_T.Employeeld AND Rank== 1.0 ORDER BY Employee Name; a. By what attributes should indexes be defined to speed up this query? Give the reasons for each attribute selected. b. Write SQL commands to create indexes for each attri- bute you identified in part a