Consider the following premises. ~p_15. p_15 <-> w_4. s -> w_4. s or t_4. Can we infer q or t_4 from them?
 From p_15 <-> w_4, ~p_15 we can infer ~w_4. From s -> w_4, ~w_4 we can infer ~s. From ~s we can infer ~s or q. Finally, from ~s or q, s or t_4 we can infer q or t_4. Therefore, the answer is yes.