3. Consider the following 2-CNF formula:

F = (-a V b)^(-bVc) ^ (cV b) ^ (bV-d) ^ (e Vb) ^ (Ve)

• 3a. Draw the digraph corresponding to F.

•3b. Use the digraph to prove that F is satisfiable, and find a satisfying assignment to F.

• 3c. Further use the digraph to list all satisfying assignments to F.