What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? forall x_4: R(x_4) -> P_4(x_4). forall x_4: ~R(x_4). forall x_4: P_4(x_4) <-> R(x_4).
forall x_4: P_4(x_4) -> R(x_4). forall x_4: R(x_4) -> P_4(x_4). forall x_4: ~P_4(x_4).