Consider the following premises. q_11 -> t_2. q_2. t_2 -> ~q_2. t_2 -> q_11. Can we infer ~q_11 from them? If possible, name the inference rules being used at each step.
 From t_2 -> q_11, q_11 -> t_2 we can infer t_2 <-> q_11 via biconditional introduction. From t_2 <-> q_11 we can infer q_11 -> t_2 via biconditional elimination. From t_2 -> ~q_2, q_2 we can infer ~t_2 via modus tollens. Finally, from q_11 -> t_2, ~t_2 we can infer ~q_11 via modus tollens. Therefore, the answer is yes.