Consider the following premises. s -> t_4. q_3 -> t_4. s or q_3. t_4 -> q. Can we infer q from them?
 From s -> t_4, q_3 -> t_4, s or q_3 we can infer t_4. Finally, from t_4 -> q, t_4 we can infer q. Therefore, the answer is yes.