Consider the following premises. forall x_4: P_6(x_4) -> T(x_4). forall x_6: P_6(x_6). Can we infer T(f) from them? If possible, name the inference rules being used at each step.
 From forall x_6: P_6(x_6) we can infer P_6(f) via universal instantiation. From forall x_4: P_6(x_4) -> T(x_4) we can infer P_6(f) -> T(f) via universal instantiation. Finally, from P_6(f) -> T(f), P_6(f) we can infer T(f) via modus ponens. Therefore, the answer is yes.