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LNAME SSN BDATE EMPLOYEE FNAME MINIT John B Franklin T Alicia J Jennifer S Ramesh K Joyce A Ahmad V James E Smith Wong Zelaya Wallace Narayan English Jabbar Borg 123456789 333445555 999887777 987654321 666884444 453453453 987987987 888665555 1965-01-09 1955-12-08 1968-07-19 1941-06-20 1962-09-15 1972-07-31 1969-03-29 1937-11-10 ADDRESS 731 Fondren, Houston, TX 638 Voss, Houston, TX 3321 Castle, Spring, TX 291 Berry, Bellaire, TX 975 Fire Oak, Humble, TX 5631 Rice, Houston, TX 980 Dallas, Houston, TX 450 Stone, Houston, TX SEX SALARY M 30000 M 40000 F 25000 F 43000 M 38000 F 25000 M 25000 M 55000 SUPERSSN DNO 333445555 5 888665555 5 987654321 4 888665555 4 333445555 5 333445555 5 987654321 4 null 1 DEPT_LOCATIONS DNUMBER 1 4 5 5 5 DLOCATION Houston Stafford Bellaire Sugarland Houston DEPARTMENT DNAME Research Administration Headquarters DNUMBER 5 4 MGRSSN 333445555 987654321 888665555 MGRSTARTDATE 1988-05-22 1995-01-01 1981-06-19 1 WORKS_ON PNO 1 PROJECT HOURS 32.5 7.5 40.0 20.0 20.0 10.0 10.0 10.0 10.0 30.0 PNUMBER PLOCATION DNUM 1 5 ESSN 123456789 123456789 666884444 453453453 453453453 333445555 333445555 333445555 333445555 999887777 999887777 987987987 987987987 987654321 987654321 888665555 2 3 1 2 2 3 10 20 30 10 10 5 PNAME ProductX ProductY Productz Computerization Reorganization Newbenefits 2 3 10 20 30 Bellaire Sugarland Houston Stafford Houston Stafford 5 4 1 4 10.0 35.0 5.0 30 30 20 20 20.0 15.0 null DEPENDENT ESSN DEPENDENT NAME SEX BDATE F M F 333445555 333445555 333445556 987654321 123456789 123456789 123456789 Alice Theodore Joy Abner Michael Alice Elizabeth RELATIONSHIP DAUGHTER SON SPOUSE SPOUSE SON DAUGHTER SPOUSE 1986-04-05 1983-10-25 1958-05-03 1942-02-28 1988-01-04 1988-12-30 1967-05-05 M M F F Specify the following queries on the database schema shown in above Figure using the relational algebra discussed in cla 1. Retrieve the names of employees who work on the 'Computerization' project. 2. Find the names of employees that works for 'Research' department 3. Retrieve the names of department managers who do not work on any project. 4. Find the names and addresses of employees who work on at least one project located in Stafford