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 y: T(y) -> P(y). forall y: S_2(y) <-> T(y). forall y: P(y) -> S_2(y). exists y: ~P(y).
exists y: ~T(y) can be inferred via the existential modus tollens rule. forall y: T(y) -> S_2(y) can be inferred via the universal transitivity rule. forall y: S_2(y) -> T(y) can be inferred via the universal biconditional elimination rule. forall y: T(y) -> S_2(y) can be inferred via the universal biconditional elimination rule.