Consider the following premises. p_10 -> q_14. r. q_18. q_14 -> p_10. u_2 <-> q_14. u_2 -> ~q_18. Can we infer r and ~p_10 from them? If possible, name the inference rules being used at each step.
 From u_2 -> ~q_18, q_18 we can infer ~u_2 via modus tollens. From u_2 <-> q_14, ~u_2 we can infer ~q_14 via biconditional elimination. From p_10 -> q_14, q_14 -> p_10 we can infer p_10 <-> q_14 via biconditional introduction. From p_10 <-> q_14, ~q_14 we can infer ~p_10 via biconditional elimination. Finally, from r, ~p_10 we can infer r and ~p_10 via conjunction. Therefore, the answer is yes.