Figure 4

a.
Enter Action Code (? for help): c

   There are 6 nodes

Enter Action Code (? for help}: f

   Tree depth is 4

Enter Action Code (? for help): p

      1 black      L: -          R: -
      2 blue       L: black      R: brown
      3 brown      L: -          R: cherry
      4 cherry     L: -          R: -
      5 green      L: blue       R: red
      6 red        L: -          R: -

b.
           green             (1)
          /     \
    blue         red         (2)
   /    \
black  brown                 (3)
          \
        cherry               (4)