Consider the following premises. w <-> q. t_3 -> w. q -> t_3. Can we infer w <-> t_3 from them?
 From w <-> q we can infer w -> q. From w -> q, q -> t_3 we can infer w -> t_3. Finally, from w -> t_3, t_3 -> w we can infer w <-> t_3. Therefore, the answer is yes.