1. The problem statement, all variables and given/known data Are these system specifications consistent? "Whenever the system software is being upgraded, users cannot access the file system. If users can access the file system, then they can have new files, then the system software is not being upgraded." 2. Relevant equations p: The system software is being upgraded q: Users cannot access the file system r: users can save new files. 3. The attempt at a solution My professor did not really explain what consistency was. So I am unsure of how to go about doing this problem. I did some searching on this same problem and found that p→⇁q I don't quite understand why that is. Can someone please help?