SELECT title FROM course WHERE course_id IN (SELECT T1.prereq_id FROM prereq AS T1 JOIN course AS T2 ON T1.course_id  =  T2.course_id WHERE T2.title  =  'Mobile Computing')
What is the title of the course that is a prerequisite for Mobile Computing?
SELECT title FROM course WHERE course_id IN ( SELECT T1.prereq_id FROM prereq AS T1 JOIN course AS T2 ON T1.course_id = T2.course_id WHERE T2.title = 'Mobile Computing ' )
select title from course where course_id in ( select t1 . prereq_id from prereq as t1 join course as t2 on t1 . course_id = t2 . course_id where t2 . title = value )
What is the title of the course that is a prerequisite for Mobile Computing ?