Given that it is 3NF
1. All attributes contribute to the primary key
No need, let take R(A,B,C,D) and FD's are {A → BCD}
this is in 3NF but all attributes didn't contribute to the primary key
2.Each non-key attribute determines the primary key
Always False, if Attributes determines Primary Key, it is called as Candidate Key but not as Non-key
3. Each non-key attribute is determined by the primary key
Always true.
4. Every determinant is a candidate key
this statement conveying that in X → Y, X should be Candidate Key, it is for BCNF, for 3NF it is not necessary.
5.The relation is not in fourth normal form.
It is Not in syllabus, No comments on this statement.