Write SQL queries based on the following database Schema:

classroom(building, room_number, capacity)

department(dept_name, building, budget)

course(course_id, title, dept_name, credits)

instructor(ID, name, dept_name, salary)

section(course_id, sec_id, semester, year, building, room_number, time_slot_id)

teaches(ID, course_id, sec_id, semester, year)

student(ID, name, dept_name, tot_cred)

takes(ID, course_id, sec_id, semester, year, grade)

advisor(s_ID, i_ID)

time_slot(time_slot_id, day, start_time, end_time)

prereq(course_id, prereq_id)

Please submit your queries through Blackboard.

1.Find the sections (i.e. course_id and section_id) that had the maximum enrollment in Fall 2009.

(Use set operation EXCEPT, INTERSECT or use subqueries)

2. Find the IDs and names of all students who have not taken any course offering before Spring 2009.

3. Find the IDs and names of all students who have taken a computer science course and a biology course.