What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? forall z: U(z) <-> T(z). forall z: T(z) or R_1(z). forall z: ~U(z).
forall z: U(z) -> T(z). forall z: T(z) -> U(z). forall z: ~T(z).