2. We are given the following relational database schema for a database that keeps track of student enrollment in courses and the books adopted for each course. STUDENT COURSE Ssn Name Major Bdate Course# | Cname | Dept ENROLL BOOK_ADOPTION Ssn | Course# | Semester | Grade Course# | Semester | Book.ISBN TEXTBOOK ISBN Title Publisher Author a. Consider the COURSE relation. Assuming that names of courses are unique, list all the superkeys, keys, candidate keys, and select a primary key. i. Superkeys: ii. Keys: iii. Candidate keys