Translate the following inference to logic notation: For all x, x_11 is a bartender if and only if x_11 will drink water. For all x, if x_11 drinks water, then x_11 is climbing a mountain. There is at least one x for which x_11 will not climb a mountain. Therefore there is at least one x for which x_11 is not a bartender.
forall x: P(x) <-> Q(x). forall x: Q(x) -> R(x). exists x: ~R(x). Therefore exists x: ~P(x).