Translate the following inference to logic notation: For all x, if x_11 plays squash, then x_11 is drinking water. For all x, x_11 will sleep if and only if x_11 will play squash. There is at least one x for which x_11 will not drink water. Therefore there is at least one x for which x_11 will not sleep.
forall x: P(x) -> Q(x). forall x: R(x) <-> P(x). exists x: ~Q(x). Therefore exists x: ~R(x).