Consider the following premises. w_3 <-> q_3. ~t_3. q_3 or s. t_3 <-> w_3. Can we infer ~s from them?
 From t_3 <-> w_3, ~t_3 we can infer ~w_3. From w_3 <-> q_3, ~w_3 we can infer ~q_3. Finally, from q_3 or s, ~q_3 we can infer s, which contradicts ~s. Therefore, the answer is no.