Consider the following premises. t_1 -> r_1. p_4 or t_1. ~r_1 or s_2. ~w or r. p_4 -> r_1. Can we infer s_2 or r from them?
 From p_4 -> r_1, t_1 -> r_1, p_4 or t_1 we can infer r_1. From r_1 we can infer r_1 or w. From r_1 or w, ~r_1 or s_2 we can infer w or s_2. Finally, from w or s_2, ~w or r we can infer s_2 or r. Therefore, the answer is yes.