State True or false

1. Query processing is more efficient in a schema in a higher normal form than in a lower normal form, since the higher normal form causes smaller relations.
2. Functional dependencies in a given relation cannot be changed after updates of tuples.
3. If 1NF relation R does not have composite keys, then R is in 2NF.
4. XY ZWV can be decomposed into X ZW and Y ZW.
5. Denormalization can be performed from beginning of the database development.