What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? exists y: ~Q(y). forall y: S_4(y) <-> T_2(y). forall y: T_2(y) <-> Q(y).
forall y: S_4(y) -> T_2(y). forall y: T_2(y) -> Q(y). forall y: T_2(y) -> S_4(y). forall y: Q(y) -> T_2(y). exists y: ~T_2(y).