Translate the following inference to logic notation: For all x, x_11 will listen to a song or x_11 will go running. For all x, x_11 is rich or x_11 will not play squash. For all x, if x_11 listens to a song, then x_11 is playing squash. There is at least one x for which x_11 will go running if and only if x_11 is rich. Therefore there is at least one x for which x_11 is rich.
forall x: P(x) or Q(x). forall x: R(x) or ~S(x). forall x: P(x) -> S(x). exists x: Q(x) <-> R(x). Therefore exists x: R(x).