SELECT
  salary,grade_level
FROM
  employees e
JOIN
  job_grades g
ON
  e.`salary` BETWEEN g.`lowest_sal` AND g.`lowest_sal`;

SELECT
  COUNT(*),grade_level
FROM
  job_grades j
JOIN
  employees e
ON
  e.`salary` BETWEEN j.`lowest_sal`AND j.`highest_sal`
GROUP BY
  grade_level DESC;

SELECT last_name,department_name
FROM employees e
INNER JOIN departments d
ON e.department_id=d.department_id;

SELECT last_name,job_title
FROM employees e
INNER JOIN jobs j
ON e.job_id=j.job_id
WHERE e.last_name LIKE ‘%e%';