Consider the following premises. r or t. t -> p_2. ~r or p_3. p_2 or ~p_3. Can we infer ~p_2 from them?
 From r or t, ~r or p_3 we can infer t or p_3. From p_2 or ~p_3 we can infer p_3 -> p_2. Finally, from t -> p_2, p_3 -> p_2, t or p_3 we can infer p_2, which contradicts ~p_2. Therefore, the answer is no.