What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? s -> p_11. s -> r_4. p_11 <-> q_11. ~q_11. r_4 -> s.
r_4 -> p_11. s <-> r_4. r_4 <-> s. p_11 -> q_11. q_11 -> p_11. ~p_11.