What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? exists z_3: R_1(z_3) or ~S_4(z_3). forall z_3: P(z_3) -> U(z_3). forall z_3: Q(z_3) -> P(z_3). forall z_3: U(z_3) -> S_4(z_3).
forall z_3: P(z_3) -> S_4(z_3). forall z_3: Q(z_3) -> U(z_3). exists z_3: S_4(z_3) -> R_1(z_3).