• Prove that a common enemy graph is a competition graph (hint: figure out what it is the competition graph of).
• Verify (set theoretically) that the domination graph of a tournament T is the complement of the competition graph of the reversal of T.
• Do problems 5 and 6 on page 135 of R.
• Do the following problems on p. 153 of R: 3,4,5,8,11,12,13,16.

Quiz 6 - due Wednesday Feb. 20

1. R, p. 153, # 8
2. R, p. 153, #12
3. R, p. 153, #16