Consider the following premises. q_2 <-> s_1. q_2 <-> q. s_1 -> ~u_2. u_2. Can we infer q from them?
 From s_1 -> ~u_2, u_2 we can infer ~s_1. From q_2 <-> s_1, ~s_1 we can infer ~q_2. Finally, from q_2 <-> q, ~q_2 we can infer ~q, which contradicts q. Therefore, the answer is no.