Translate the following inference to logic notation: For all x, y will play squash if and only if y will go running. For all x, y will play squash or y will not go running. Therefore for all x, y will go running if and only if y will play squash.
forall x: P(x) <-> Q(x). forall x: P(x) or ~Q(x). Therefore forall x: Q(x) <-> P(x).