4. Find the names and IDs of all students who have taken a course taught by Dr. Who. Use at least one natural join in your answer.

5. Find the department and course id of all classes that were taught or are being taught by an instructor from a different department. Use at least one set operations ( union, intersection, or -) in your query.

6. Find the name and ID of all students who are taking all of the courses that Dr. Who is teaching in the Spring 2020 semester.

7. Find the IDs of all students who have taken all of the CMPSC courses. Use the division operation.

8. Do the same operation as in problem 7, using only fundamental operations.

Can you solve 4,5,6,7,8?

I tried it and it seems wrong.

this is a data design

I just want to write it in relation

something like department, course id ( year = "2020"(section))

student takes ID course id sec id semester year grade ID name dept_name tot_cred section course advisor course id sec id semester year building room_number time_slot_id course id title dept_name credits department dept name building budget sid i_id time slot time slot_id day start_time end_time instructor classroom prereq course id prereq id building room_number capacity ID name dept_name salary teaches ID course id sec id semester year student takes ID course id sec id semester year grade ID name dept_name tot_cred section course advisor course id sec id semester year building room_number time_slot_id course id title dept_name credits department dept name building budget sid i_id time slot time slot_id day start_time end_time instructor classroom prereq course id prereq id building room_number capacity ID name dept_name salary teaches ID course id sec id semester year