What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? forall x_12: R(x_12) -> Q_9(x_12). forall x_12: Q_9(x_12) -> R(x_12). exists x_12: R(x_12) or ~S(x_12). forall x_12: Q_9(x_12) -> S(x_12).
forall x_12: R(x_12) -> S(x_12). exists x_12: S(x_12) -> R(x_12). forall x_12: R(x_12) <-> Q_9(x_12). forall x_12: Q_9(x_12) <-> R(x_12).