Translate the following inference to logic notation: For all x, if x_6 were a janitor, then x_6 is fast. For all x, if x_6 were a janitor, then x_6 is fast. For all x, if x_6 were fast, then x_6 is a janitor. For all x, x_6 is not fast. Therefore for all x, x_6 is not a janitor.
forall x: P(x) -> Q(x). forall x: P(x) -> Q(x). forall x: Q(x) -> P(x). forall x: ~Q(x). Therefore forall x: ~P(x).