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 x: S(x) -> R(x). forall x: R(x) -> T(x). forall x: T(x) <-> S(x). exists x: ~T(x).
exists x: ~R(x) can be inferred via the existential modus tollens rule. forall x: S(x) -> T(x) can be inferred via the universal transitivity rule. forall x: T(x) -> S(x) can be inferred via the universal biconditional elimination rule. forall x: S(x) -> T(x) can be inferred via the universal biconditional elimination rule. exists x: ~S(x) can be inferred via the existential biconditional elimination rule.