What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? forall y_3: T_2(y_3) <-> Q_2(y_3). forall y_3: Q_2(y_3) -> T_2(y_3). forall y_3: T_2(y_3) -> Q_2(y_3).
forall y_3: Q_2(y_3) <-> T_2(y_3). forall y_3: T_2(y_3) <-> Q_2(y_3). forall y_3: T_2(y_3) -> Q_2(y_3). forall y_3: Q_2(y_3) -> T_2(y_3).