What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? exists x_4: W(x_4) <-> U_2(x_4). forall x_4: W(x_4).
exists x_4: W(x_4) -> U_2(x_4). exists x_4: U_2(x_4) -> W(x_4).