What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? forall z_2: T_4(z_2) <-> S(z_2). exists z_2: S(z_2) <-> T_4(z_2).
forall z_2: T_4(z_2) -> S(z_2). exists z_2: S(z_2) -> T_4(z_2). forall z_2: S(z_2) -> T_4(z_2). exists z_2: T_4(z_2) -> S(z_2).