What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? forall z_2: U(z_2) -> P_3(z_2). forall z_2: U(z_2) <-> P_3(z_2).
forall z_2: U(z_2) -> P_3(z_2). forall z_2: P_3(z_2) -> U(z_2).