Translate the following inference to logic notation: For all x, x_8 is a mechanic or x_8 is not a janitor. For all x, x_8 is fast if and only if x_8 is a mechanic. Therefore for all x, if x_8 were a janitor, then x_8 is fast.
forall x: P(x) or ~Q(x). forall x: R(x) <-> P(x). Therefore forall x: Q(x) -> R(x).