Q11: The figure below illustrates a file system that needs to be backed up. Assume that we are not using physical dump. Explain the four phases of the logical dumping algorithm using the figure below and give the state of the needed data structure at each stage. (Squares are directories, circles are files. Shaded items have been modified since the last dump (3.8,9,16,17,20,21,22)) (5 points) Root directory 2 16 18 27 4 17 19 28) 29 Directory that has not-7 10 20 30 changed 9 114 21 23 31) (32