272 Logic as a Tool Section 2.3 2.3.1 (a) The formula is not a tautology: ((p → q) → q) → q : F (p → q) → q : T , q : F p→ q:F q:T × p : T, q : F (c) Tautology: ((p → q) ∧ (p → ¬q)) → ¬p : F (p → q) ∧ (p → ¬q) : T , ¬p : F p:T p → q : T , p → ¬q : T p:F × q:T p:F × ¬q : T q:F ×