Problem
1. Why are file system permissions so important in the Linux DAC model? How do they relate or map to the concept of "subject-action-object" transactions?
2. User "ahmed" owns a directory, "stuff," containing a text file called "ourstuff.txt" that he shares with users belonging to the group "staff." Those users may read and change this file, but not delete it. They may not add other files to the directory. Others may neither read, write, nor execute anything in "stuff." What would appropriate ownerships and permissions for both the directory "stuff" and the file "ourstuff.txt" look like? (Write your answers in the form of "long listing" output.)