Consider the following premises. forall z_1: W(z_1) <-> R(z_1). q_1 -> R(a_9). R(a_9) -> q_1. ~W(a_9). Can we infer q_1 from them? If possible, name the inference rules being used at each step.
 From forall z_1: W(z_1) <-> R(z_1) we can infer W(a_9) <-> R(a_9) via universal instantiation. From W(a_9) <-> R(a_9), ~W(a_9) we can infer ~R(a_9) via biconditional elimination. From R(a_9) -> q_1, q_1 -> R(a_9) we can infer R(a_9) <-> q_1 via biconditional introduction. Finally, from R(a_9) <-> q_1, ~R(a_9) we can infer ~q_1 via biconditional elimination, which contradicts q_1. Therefore, the answer is no.