Question 2 Use truth tables to show the following:
(a) whether ¬p ∧ ¬(p → q) is a tautology, a contradiction or neither.
(b) whether ((p → q) ∧ (p → r)) → (p →) (q ∧ r)) is a tautology, a contradiction or neither.
(c) ¬(¬p ∧ q) and q → p are logically equivalent.
(d) (p → (q → r)) and (q → (p → r)) are logically equivalent.