1. What are all details about the oldest employee, using uncorrelated subquery. 12. What are all details about the oldest employee, using correlated subquery. 13. What are the details about projects, which employees either are assigned to or apply skills on, without using subquery? 14. What are the details about projects, which employees either are assigned to or apply skills on, using subquery? 15. What are the numbers of project assignments for all possible combinations of employees and then cities? (Hint: This is an OLAP query using GROUP BY CUBE.)