Translate the following inference to logic notation: There is at least one x for which x_9 is a writer if and only if x_9 will drink water. For all x, x_9 is not poor. For all x, x_9 is a writer or x_9 will take a plane. For all x, if x_9 drinks water, then x_9 is poor. Therefore there is at least one x for which x_9 will take a plane.
exists x: P(x) <-> Q(x). forall x: ~R(x). forall x: P(x) or S(x). forall x: Q(x) -> R(x). Therefore exists x: S(x).