Consider the following premises. r_3 -> ~q_2. r_3 -> p_6. p_6 -> r_3. q_2. Can we infer p_6 from them?
 From p_6 -> r_3, r_3 -> p_6 we can infer p_6 <-> r_3. From r_3 -> ~q_2, q_2 we can infer ~r_3. Finally, from p_6 <-> r_3, ~r_3 we can infer ~p_6, which contradicts p_6. Therefore, the answer is no.