Q_Dept

SELECT TO_CHAR(HIREDATE, 'YY') YEAR, DEPTNO
FROM EMP
GROUP BY TO_CHAR(HIREDATE, 'YY'), DEPTNO
ORDER BY TO_CHAR(HIREDATE, 'YY'), DEPTNO

Q_Job

SELECT DISTINCT JOB
FROM EMP

Q_Salary

SELECT TO_CHAR(HIREDATE, 'YY') YEAR,  DEPTNO,  JOB,
SUM(SAL) FROM EMP
GROUP BY TO_CHAR(HIREDATE, 'YY'),  DEPTNO,  JOB
ORDER BY TO_CHAR(HIREDATE, 'YY'),  DEPTNO,  JOB