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: P_2(z) -> R_2(z). forall z: S_2(z) <-> P_2(z). forall z: R_2(z) -> P_2(z). forall z: T(z). forall z: S_2(z) -> ~T(z).
forall z: ~S_2(z) can be inferred via the universal modus tollens rule. forall z: P_2(z) <-> R_2(z) can be inferred via the universal biconditional introduction rule. forall z: R_2(z) <-> P_2(z) can be inferred via the universal biconditional introduction rule. forall z: S_2(z) -> P_2(z) can be inferred via the universal biconditional elimination rule. forall z: P_2(z) -> S_2(z) can be inferred via the universal biconditional elimination rule.