Translate the following inference to logic notation: For all x, x_12 will listen to a song or x_12 will play tennis. There is at least one x for which if x_12 listens to a song, then x_12 is playing squash. For all x, x_12 will play tennis if and only if x_12 will play squash. For all x, if x_12 climbs a mountain, then x_12 is not playing squash. Therefore there is at least one x for which x_12 will not climb a mountain.
forall x: P(x) or Q(x). exists x: P(x) -> R(x). forall x: Q(x) <-> R(x). forall x: S(x) -> ~R(x). Therefore exists x: ~S(x).