Which of the following identities hold true whenever E and F are subsets of a set S? (complements are taken in S. There may be more than one correct answer.

1. (E^c)^c = E

2. E^c F^c = (E F)^c

3. E \ F = E F^c

4. E F = (F \ E (E F)

5. F \ E = E \ F

6. (E \ F)^c = F \ E