Consider the following premises. ~q_15. w -> q_15. w <-> q_15. Can we infer w from them?
 From w <-> q_15 we can infer q_15 -> w. From q_15 -> w, w -> q_15 we can infer q_15 <-> w. Finally, from q_15 <-> w, ~q_15 we can infer ~w, which contradicts w. Therefore, the answer is no.