What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Name the inference rule being used: forall x_14: Q_14(x_14) -> S(x_14). ~S(a_13). forall x_14: S(x_14) -> Q_14(x_14). w_1.
~S(a_13) and w_1 can be inferred via the conjunction rule. w_1 and ~S(a_13) can be inferred via the conjunction rule. forall x_14: Q_14(x_14) <-> S(x_14) can be inferred via the universal biconditional introduction rule. forall x_14: S(x_14) <-> Q_14(x_14) can be inferred via the universal biconditional introduction rule.