Consider the following premises. w_4 <-> r. ~r. w_4 <-> q. Can we infer ~q from them?
 From w_4 <-> r we can infer w_4 -> r. From w_4 -> r, ~r we can infer ~w_4. Finally, from w_4 <-> q, ~w_4 we can infer ~q. Therefore, the answer is yes.