Consider the following premises. q_2. t -> t_4. t_4 -> t. t_4 -> ~q_2. Can we infer ~t from them?
 From t_4 -> t, t -> t_4 we can infer t_4 <-> t. From t_4 <-> t we can infer t -> t_4. From t_4 -> ~q_2, q_2 we can infer ~t_4. Finally, from t -> t_4, ~t_4 we can infer ~t. Therefore, the answer is yes.