Translate the following inference to logic notation: For all x, if x_5 climbs a mountain, then x_5 is taking a plane. For all x, if x_5 takes a plane, then x_5 is playing a game. There is at least one x for which x_5 will climb a mountain. For all x, if x_5 plays a game, then x_5 is a taxi driver. Therefore there is at least one x for which x_5 is a taxi driver.
forall x: P(x) -> Q(x). forall x: Q(x) -> R(x). exists x: P(x). forall x: R(x) -> S(x). Therefore exists x: S(x).