Consider the following premises. q_7. p_1 -> u. u -> ~q_7. r <-> p_1. Can we infer ~r from them?
 From u -> ~q_7, q_7 we can infer ~u. From p_1 -> u, ~u we can infer ~p_1. Finally, from r <-> p_1, ~p_1 we can infer ~r. Therefore, the answer is yes.