Translate the following inference to logic notation: For all x, x_9 will play squash if and only if x_9 will read a book. There is at least one x for which x_9 will play squash if and only if x_9 is a soldier. For all x, x_9 is a soldier or x_9 will read a book. Therefore there is at least one x for which x_9 will play squash.
forall x: P(x) <-> Q(x). exists x: P(x) <-> R(x). forall x: R(x) or Q(x). Therefore exists x: P(x).