Consider the following premises. u <-> R_10(a_10). u <-> q. forall x_10: ~R_10(x_10). Can we infer ~q from them? If possible, name the inference rules being used at each step.
 From forall x_10: ~R_10(x_10) we can infer ~R_10(a_10) via universal instantiation. From u <-> R_10(a_10), ~R_10(a_10) we can infer ~u via biconditional elimination. Finally, from u <-> q, ~u we can infer ~q via biconditional elimination. Therefore, the answer is yes.