$$ students$($sid$,$name,age,gpa$)$

$$ courses$($cid$,$deptid, description$)$

$$ professors$($ssn$,$name,address,phone,deptid$)$

$$ enrollment$($sid$,$cid,section,grade$).$ cid makes reference to the courses table.

$$ teaches$($cid$,$section,ssn$).$ cid, section makes reference to the enrollment table

Provide SQL instructions for each of the following questions

$2.$ Find the name of professors that work for the cs department.

$3.$ Find those students $($sid$)$ enrolled in courses in the cs department.

$4.$ List ssn and name of professors that work for the cs department, but are not teaching any cs

courses.