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: forall z_3: W_2(z_3) -> U(z_3). forall z_3: W_2(z_3) <-> P(z_3). exists z_3: ~U(z_3).
exists z_3: ~W_2(z_3) can be inferred via the existential modus tollens rule. forall z_3: W_2(z_3) -> P(z_3) can be inferred via the universal biconditional elimination rule. forall z_3: P(z_3) -> W_2(z_3) can be inferred via the universal biconditional elimination rule.