Consider the following premises. forall x: W(x) or Q(x). u <-> W(d). Q(d) -> u. Can we infer u from them?
 From forall x: W(x) or Q(x) we can infer W(d) or Q(d). From u <-> W(d) we can infer W(d) -> u. Finally, from W(d) -> u, Q(d) -> u, W(d) or Q(d) we can infer u. Therefore, the answer is yes.