Consider the following premises. forall x_5: T(x_5) -> Q_3(x_5). forall x_5: T(x_5). forall x_5: P(x_5) <-> Q_3(x_5). Can we infer forall x_5: Q_3(x_5) from them? If possible, name the inference rules being used at each step.
 From forall x_5: T(x_5) we can infer forall x_5: T(x_5) or P(x_5) via universal addition. From forall x_5: P(x_5) <-> Q_3(x_5) we can infer forall x_5: P(x_5) -> Q_3(x_5) via universal biconditional elimination. Finally, from forall x_5: T(x_5) -> Q_3(x_5), forall x_5: P(x_5) -> Q_3(x_5), forall x_5: T(x_5) or P(x_5) we can infer forall x_5: Q_3(x_5) via universal disjunction elimination. Therefore, the answer is yes.