Consider the following premises. forall z_4: S(z_4). forall z_4: Q_2(z_4) -> ~S(z_4). Can we infer forall z_4: ~Q_2(z_4) from them? If possible, name the inference rules being used at each step.
We can infer forall z_4: ~Q_2(z_4) via the universal modus tollens rule. Therefore, the answer is yes.