Translate the following inference to logic notation: For all x, if x_2 were a taxi driver, then x_2 is an artist. For all x, if x_2 were an artist, then x_2 is rich. There is at least one x for which x_2 is not rich. For all x, if x_2 were rich, then x_2 is a taxi driver. Therefore there is at least one x for which x_2 is not an artist.
forall x: P(x) -> Q(x). forall x: Q(x) -> R(x). exists x: ~R(x). forall x: R(x) -> P(x). Therefore exists x: ~Q(x).