What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? forall y_3: P(y_3) -> Q(y_3). forall y_3: Q(y_3) -> P(y_3). exists y_3: ~Q(y_3).
exists y_3: ~P(y_3). forall y_3: P(y_3) <-> Q(y_3). forall y_3: Q(y_3) <-> P(y_3).