21.   A year ago, the rules changed forever for technology companies.

22.   Accustomed to cautious but prosperous lives, Iranian Jews now wonder if the rules have changed.

23.   After that, the rules could change dramatically.

24.   After midnight, the rules change for receiving Arizona tax rebates for the purchase of vehicles that can run on natural gas, propane or electricity.

25.   All the rules changed.

26.   But a Powell victory would have been an irrefutable sign that the rules had changed.

27.   But at many other companies, the rules are changing.

28.   But as even the once-rebellious Walton learned, the rules change at the top level.

29.   But if museum directors agree that the rules have changed for future acquisitions, they are not in complete harmony about what to do about the past.

30.   But Paxson executives argued Tuesday that NBC would not be able to complete the acquisition even if the rules changed.