What is the id of the prerequisite of International Finance?
select t2.prereq_id from course as t1 join prereq as t2 on t1.course_id = t2.course_id where t1.title = 'International Finance'
What are the ids of students who have taken this course?
select t1.id from student as t1 join takes as t2 on t1.id = t2.id where t2.course_id in (select t4.prereq_id from course as t3 join prereq as t4 on t3.course_id = t4.course_id where t3.title = 'International Finance')
What are their names?
select t1.name from student as t1 join takes as t2 on t1.id = t2.id where t2.course_id in (select t4.prereq_id from course as t3 join prereq as t4 on t3.course_id = t4.course_id where t3.title = 'International Finance')