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: P(z_4) -> U(z_4). forall z_4: U(z_4) -> P(z_4). forall z_4: P(z_4) -> R_1(z_4). forall z_4: R_1(z_4) -> P(z_4). forall z_4: ~R_1(z_4).
forall z_4: ~P(z_4) can be inferred via the universal modus tollens rule. forall z_4: U(z_4) -> R_1(z_4) can be inferred via the universal transitivity rule. forall z_4: R_1(z_4) -> U(z_4) can be inferred via the universal transitivity rule. forall z_4: P(z_4) <-> U(z_4) can be inferred via the universal biconditional introduction rule. forall z_4: U(z_4) <-> P(z_4) can be inferred via the universal biconditional introduction rule. forall z_4: P(z_4) <-> R_1(z_4) can be inferred via the universal biconditional introduction rule. forall z_4: R_1(z_4) <-> P(z_4) can be inferred via the universal biconditional introduction rule.