What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? forall z_4: P(z_4) <-> S(z_4). forall z_4: P(z_4) -> S(z_4). exists z_4: ~S(z_4).
exists z_4: ~P(z_4). forall z_4: P(z_4) -> S(z_4). forall z_4: S(z_4) -> P(z_4). exists z_4: ~P(z_4).