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: R(z) -> W(z). forall z: W(z) -> R(z). forall z: W(z) -> R(z).
forall z: R(z) <-> W(z) can be inferred via the universal biconditional introduction rule. forall z: R(z) <-> W(z) can be inferred via the universal biconditional introduction rule. forall z: W(z) <-> R(z) can be inferred via the universal biconditional introduction rule. forall z: W(z) <-> R(z) can be inferred via the universal biconditional introduction rule.