What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? r_3 -> s. r_3 <-> q_12. ~q_12. s -> r_3. q_12 -> r_3.
q_12 -> s. r_3 <-> s. s <-> r_3. r_3 -> q_12. q_12 -> r_3. ~r_3.