- Show Ο U Ο β‘ Ο R (Ο β¨ Ο) β§ FΟ using semantic equivalences.
- Give a model M = (S,β,L) and s β S such that M,s |= AF(Ο β¨ Ο) but M,s 6|= AFΟ β¨ AFΟ.
- Express the following statement in CTLβ:
βthe event p is never true between the events q and r on a path.β
- Show AGFp and AGEFp specify different properties.



