Consider the following premises. s_4 <-> r_3. s_4 and q. Can we infer ~r_3 from them?
 From s_4 and q we can infer s_4. From s_4 <-> r_3 we can infer s_4 -> r_3. Finally, from s_4 -> r_3, s_4 we can infer r_3, which contradicts ~r_3. Therefore, the answer is no.