Consider the following database tables and answer queries using SQL.

a) Consider the following database tables and answer queries using SQL.
Student (snum, sname, major, age)
Faculty (fid, fname, deptname)
Course (cname, meets_at, room, fid)
Enrolled (snum, cname)
i) Find the names of the students who have enrolled in course Database Systems.
ii) Find all the courses which are NOT using room R128.
iii) Find all the students who are in any of the courses that professor “Ajay Kumar” teaches.