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 z: S(z). exists z: S_1(z) <-> S(z). forall z: Q_3(z).
forall z: S(z) and Q_3(z) can be inferred via the universal conjunction rule. forall z: Q_3(z) and S(z) can be inferred via the universal conjunction rule. exists z: S_1(z) -> S(z) can be inferred via the existential biconditional elimination rule. exists z: S(z) -> S_1(z) can be inferred via the existential biconditional elimination rule.