What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? forall x_9: U(x_9) -> P(x_9). forall x_9: P(x_9) -> U(x_9). forall x_9: R_2(x_9) -> Q_1(x_9). exists x_9: U(x_9) or R_2(x_9). forall x_9: Q_1(x_9) -> P(x_9).
forall x_9: R_2(x_9) -> P(x_9). forall x_9: Q_1(x_9) -> U(x_9). forall x_9: U(x_9) <-> P(x_9). forall x_9: P(x_9) <-> U(x_9).