Consider the following premises. ~r_1. ~s_4 or r_1. s_4 or q. q_1. ~q or w. Can we infer w from them?
 From s_4 or q, ~s_4 or r_1 we can infer q or r_1. From q or r_1, ~q or w we can infer r_1 or w. Finally, from r_1 or w, ~r_1 we can infer w. Therefore, the answer is yes.