What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? forall x: Q(x) or R_1(x). exists x: P(x) <-> Q(x). forall x: P(x) or ~R_1(x).
forall x: R_1(x) -> P(x). exists x: P(x) -> Q(x). exists x: Q(x) -> P(x).