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The practice of sometimes using controlled redundancy to improve the performance of queries is called a. None of the above b. Access path C. Denormalization d. Normalization In which of the following situations would it be correct to use a recursive relationship? a. When diagramming the employees who manage other employees. b. When diagramming employees who work in a department oc. When diagramming departments that are part of other departments O d. (a) and (b) e. (b) and (c) Of. (a) and (c) O g. All of the above Which one of the following Tuple Relational Calculus queries is equivalent to this English description? For every project located in 'Dallas', list the project number, the controlling department number, and the department manager's first and last name. O { e.Fname, e.Lname (3p)PROJECT() AND EMPLOYEE() AND p.plocation='Dallas' AND ((3d)(DEPARTMENT(D) AND p.Dnum=d.Dnumber AND d. Mgr_ssn=e.Ssn)) } O { Fname, Lname (3p)PROJECT() AND EMPLOYEE() AND Plocation='Dallas' AND ((3d)(DEPARTMENT(d) AND Dnum=Dnumber AND Mgr_ssn=Ssn)) } { e.Fname, e.Lname (Ep)PROJECT() AND EMPLOYEE(e) AND p.Plocation='Dallas' AND ((3d)(DEPARTMENT(d) WHERE p.Dnum=d.Dnumber AND d. Mgr_ssn=e. Ssn))} O { Fname, Lname | PROJECT() AND EMPLOYEE() AND p.plocation='Dallas' AND SELECT((DEPARTMENT(d) AND p.Dnum=d. Dnumber AND d. Mgr_ssn=e.Ssn) }