Translate the following inference to logic notation: There is at least one x for which x will drink water. For all x, if x were sad, then x is an artist. For all x, x will drink water if and only if x is an artist. Therefore there is at least one x for which x is an artist.
exists x: P(x). forall x: Q(x) -> R(x). forall x: P(x) <-> R(x). Therefore exists x: R(x).