What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? exists z: ~R_4(z). forall z: R_4(z) <-> Q(z). forall z: Q(z) -> R_4(z).
exists z: ~Q(z). forall z: R_4(z) -> Q(z). forall z: Q(z) -> R_4(z). exists z: ~Q(z).