What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Name the inference rule being used: exists z: R_4(z). forall z: U(z) or ~W(z). forall z: W(z).
exists z: R_4(z) and W(z) can be inferred via the existential conjunction rule. exists z: W(z) and R_4(z) can be inferred via the existential conjunction rule. forall z: W(z) -> U(z) can be inferred via the universal rewriting rule.