Write a relational algebra expression for each of the following operations:

c) Find the IDs of all the students who are enrolled in COMP 314 or COMP 414.

d) Find the IDs of all the students who are enrolled in both COMP 314 and COMP 414.

Consider a student database with the following schema: Students (SID, sName); Courses (cID, Name); Enrolled (sID, ID, sectID, grade) where foreign key (SID) references Students, foreign key (CID) references Courses