3. For each of the following four arguments, (i) construct a truth table for it, (ii) mark all the cases/rows in which the premises are all true, and (iii) determine whether the argument is valid or not. If an argument is not valid, (iv) mark all the cases/rows that serve as counterexamples to that argument. ~B Modus Tollens 10% ~A-Argument by Denying the Antecedent 10% -B contraposition 10% Transitivity 10%