Translate the following inference to logic notation: There is at least one x for which x_4 is not a taxi driver. For all x, x_4 will make tea. For all x, if x_4 makes tea, then x_4 is a taxi driver. Therefore there is at least one x for which x_4 will drink water.
exists x: ~P(x). forall x: Q(x). forall x: Q(x) -> P(x). Therefore exists x: R(x).