Consider the following premises. w_2 <-> q. p_9 <-> t. ~s_2. w_2 <-> p_9. s_2 <-> t. Can we infer ~q from them?
 From s_2 <-> t, ~s_2 we can infer ~t. From p_9 <-> t, ~t we can infer ~p_9. From w_2 <-> p_9, ~p_9 we can infer ~w_2. Finally, from w_2 <-> q, ~w_2 we can infer ~q. Therefore, the answer is yes.