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_4: W(z_4) -> R_1(z_4). ~R_1(a_11). forall z_4: R_1(z_4) -> W(z_4).
forall z_4: W(z_4) <-> R_1(z_4) can be inferred via the universal biconditional introduction rule. forall z_4: R_1(z_4) <-> W(z_4) can be inferred via the universal biconditional introduction rule.