Consider the following premises. w_4. forall x_9: P_9(x_9). u -> ~w_4. Can we infer P_9(a_9) and ~u from them?
 From u -> ~w_4, w_4 we can infer ~u. From forall x_9: P_9(x_9) we can infer P_9(a_9). Finally, from P_9(a_9), ~u we can infer P_9(a_9) and ~u. Therefore, the answer is yes.