11. A candidate key must uniquely identify each row.

A. True
B. False

12. Well-structured relations encourage anomalies of data.

A. True
B. False

13. A foreign key may be null and still adhere to the referential integrity constraint.

A. True
B. False

14. If a relation is in third normal form, it does not need to be in second normal form.

A. True
B. False

15. The primary key of the new relation in a many-to-many relationship is a composite key comprised of the primary keys of each of the binary entities.

A. True
B. False