SQL

5. (15 points, 5 points each) Consider the following primary keys are underlined relational schema, where the Students(sid, sname, address, dept id) Courses(cid, cname, dept id) Departments (dept id, dname, college) Grades(sid, cid year, semester, grade) Write the following queries in SQL (1) Find the sids and snames of students who have taken Database" course (.e,cname - Database') in Fall 2015 (2) Find the average grade of all the students who have taken "CscD327" (i.e., cid 'CSCD327') in Fall 2015. (3) Find the sids of students who have taken at least 10 courses offered by "Computer Science" department (i.e., dname Computer Science')