What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? forall x: T(x) -> Q_4(x). forall x: U(x) -> T(x). exists x: Q_4(x) -> T(x).
forall x: U(x) -> Q_4(x). exists x: Q_4(x) <-> T(x). exists x: T(x) <-> Q_4(x).