1) List the name of divisions that sponsors project(s) Chen works on.
2) List the name of division (d) that has employee who work on a project (p) not sponsored by this division. (hint in a corelated subquery where d.did <> p.did)
3) List the name of employee who work with Chen on some project(s). (Find an employee who works on a project that chen also works on, don't show same employee multiple times in result)
