Consider the following premises. t or q_6. q_6 -> r_2. r_2 -> q_6. t -> r_2. Can we infer r_2 from them?
 From r_2 -> q_6, q_6 -> r_2 we can infer r_2 <-> q_6. From r_2 <-> q_6 we can infer q_6 -> r_2. Finally, from t -> r_2, q_6 -> r_2, t or q_6 we can infer r_2. Therefore, the answer is yes.