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