1.
SELECT first_name, salary FROM employees WHERE salary > (SELECT salary FROM employees WHERE employee_id = 103);

2.
SELECT department_id, department_name FROM departments WHERE location_id = (SELECT location_id FROM departments WHERE department_id = 90);

3.
SELECT last_name, hire_date FROM employees WHERE hire_date > (SELECT hire_date FROM employees WHERE employee_id = 101);

4.
SELECT first_name, last_name, department_id FROM employees WHERE department_id = (SELECT department_id FROM departments WHERE department_name = 'Sales');

5.
SELECT department_id, department_name FROM departments WHERE location_id = (SELECT location_id FROM locations WHERE city = 'Toronto');

6.
SELECT first_name, salary, department_id FROM employees WHERE department_id = (SELECT department_id FROM employees WHERE employee_id = 124);

7.
SELECT first_name, salary, department_id FROM employees WHERE salary > (SELECT AVG(salary) FROM employees);

8.
SELECT first_name, salary, department_id FROM employees WHERE salary = ANY(SELECT salary FROM employees WHERE department_id = 20);

9.
SELECT first_name, salary, department_id FROM employees WHERE salary > (SELECT MAX(salary) FROM employees WHERE department_id = 50);

10.
SELECT first_name, salary, department_id FROM employees WHERE salary > (SELECT MIN(salary) FROM employees WHERE department_id = 60);

11.
SELECT first_name, salary, department_id FROM employees WHERE salary < (SELECT MIN(salary) FROM employees WHERE department_id = 90);

12.
SELECT first_name, salary, department_id FROM employees WHERE department_id = ANY(SELECT department_id FROM departments WHERE location_id = (SELECT location_id FROM locations WHERE city = 'Seattle'));

13.
SELECT first_name, salary, department_id FROM employees WHERE salary < (SELECT AVG(salary) FROM employees) AND department_id = ANY(SELECT department_id FROM employees WHERE first_name = 'Kevin')