What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? t_1 <-> p_9. ~q_9. w <-> t_1. p_9 <-> q_9.
t_1 -> p_9. w -> t_1. p_9 -> q_9. p_9 -> t_1. t_1 -> w. q_9 -> p_9. ~p_9.