Translate the following inference to logic notation: There is at least one x for which x_7 is happy or x_7 will not drink water. For all x, x_7 will play tennis. For all x, if x_7 were happy, then x_7 is not playing tennis. Therefore there is at least one x for which x_7 will not drink water.
exists x: P(x) or ~Q(x). forall x: R(x). forall x: P(x) -> ~R(x). Therefore exists x: ~Q(x).