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