What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? s_3 or q_7. s_4 <-> q_7. ~s_3 or q_4. ~q_12. s_4 <-> q_12.
q_7 or q_4. s_4 -> q_7. s_4 -> q_12. q_7 -> s_4. q_12 -> s_4. ~s_4.