Translate the following inference to logic notation: For all x, y_2 is a bartender. For all x, y_2 will climb a mountain if and only if y_2 is a taxi driver. For all x, y_2 will climb a mountain. Therefore for all x, y_2 is a taxi driver.
forall x: P(x). forall x: Q(x) <-> R(x). forall x: Q(x). Therefore forall x: R(x).