Translate the following inference to logic notation: For all x, x_7 is a writer if and only if x_7 will sleep. For all x, x_7 is not a janitor or x_7 will read a book. For all x, x_7 will not sleep. For all x, x_7 is a janitor. Therefore for all x, x_7 will read a book.
forall x: P(x) <-> Q(x). forall x: ~R(x) or S(x). forall x: ~Q(x). forall x: R(x). Therefore forall x: S(x).