Consider the following premises. w_4 -> t_3. p_4. t_3 or ~p_4. Can we infer ~t_3 from them? If possible, name the inference rules being used at each step.
 From t_3 or ~p_4 we can infer p_4 -> t_3 via rewriting. From p_4 we can infer p_4 or w_4 via addition. Finally, from p_4 -> t_3, w_4 -> t_3, p_4 or w_4 we can infer t_3 via disjunction elimination, which contradicts ~t_3. Therefore, the answer is no.