Consider the following premises. q_9. p_9 <-> q_9. p_9 -> r_1. Can we infer r_1 from them?
 From p_9 <-> q_9 we can infer q_9 -> p_9. From q_9 -> p_9, p_9 -> r_1 we can infer q_9 -> r_1. Finally, from q_9 -> r_1, q_9 we can infer r_1. Therefore, the answer is yes.