Consider the following premises. p_14 <-> s. ~q_4 or t. p_14 or u. ~s. Can we infer u or t from them?
 From p_14 <-> s, ~s we can infer ~p_14. From ~p_14 we can infer ~p_14 or q_4. From ~p_14 or q_4, p_14 or u we can infer q_4 or u. Finally, from q_4 or u, ~q_4 or t we can infer u or t. Therefore, the answer is yes.