What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? exists x: R(x) <-> U_3(x). forall x: U(x) -> R(x). forall x: R(x) -> U(x). forall x: ~U(x).
forall x: ~R(x). forall x: U(x) <-> R(x). forall x: R(x) <-> U(x). exists x: R(x) -> U_3(x). exists x: U_3(x) -> R(x).