Use sub queries to answer the following

Q1) write a query to display the employees first name and department id for all employees who work in sales department. 1 pts

Q2) write a query to find the employee who earns a salary greater than the average salaries for department 50. 1 pts

Q3) display the department names and ids that is located in the country United States of America. 1pts

Q4) display the names and salaries of employees who get a salary greater than the average between max salary and min salary for his job. 2pts