Practice 89 1. Find the average salary fot all employees. 2. Find the minimum and maximum project revenue for all acuve projecis that make muney 3. Find the number of projects that are completed. You may not use a WHLRE clause. 4. find the number of projects that have been worked on ot currently are being worked on by an employee. . rind the last name of the employee whose last name is last in cictionary order 6. Compute the employee salary standard deviation. As a reminder the formula for the pepulation slandard deviation is as follows x, -x) 7. Find the number ot employecs who are assigned to some departmen. You may no: 8. For each department, list the department code and the number of empleyees in the 0. tur each departiment that has a project, list the department code end report the 10. Mocity thc query from Problem 9 to only include departmenis with 2 or more 11. Modify the query from Problem 10 to only count active projecis. Sort the resulis in 12. Find the emplovee ID of all ensplayees where theirassigned tizme to work on projects 13. Calculate the salary cost for each deparunent with employees that don't have a last use a WHERE clause. departmerst average revenue and count of all ot its prcjects projects descending order by count is 100x or mare. name ending in re after giving everyone a 1ox raise