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