This is your prof speaking:
"DO YOUR OWN HOMEWORK YOU CHEATER!"
Seriously,
I'll give you a hint:
Try using
SELECT * FROM emp WHERE
( sal > (SELECT sal FROM emp AS EMP2 WHERE (EMP2.mgr=emp.mgr)) )
or something like that.
Use a ALIAS for the same table to distinguish them.
Hmm I am doing your homework.
Did I deserve a beer now?
;-)
Regards,
Erwin