Consider the following premises. forall x_7: T(x_7) <-> Q_7(x_7). ~Q_7(a_2). forall x_7: T(x_7) -> Q_7(x_7). Can we infer T(a_2) from them? If possible, name the inference rules being used at each step.
 From forall x_7: T(x_7) <-> Q_7(x_7) we can infer forall x_7: Q_7(x_7) -> T(x_7) via universal biconditional elimination. From forall x_7: T(x_7) -> Q_7(x_7), forall x_7: Q_7(x_7) -> T(x_7) we can infer forall x_7: T(x_7) <-> Q_7(x_7) via universal biconditional introduction. From forall x_7: T(x_7) <-> Q_7(x_7) we can infer T(a_2) <-> Q_7(a_2) via universal instantiation. Finally, from T(a_2) <-> Q_7(a_2), ~Q_7(a_2) we can infer ~T(a_2) via biconditional elimination, which contradicts T(a_2). Therefore, the answer is no.