Translate the following inference to logic notation: For all x, if y takes a plane, then y is not a janitor. For all x, y is a janitor. There is at least one x for which if y drives a car, then y is taking a plane. For all x, if y takes a plane, then y is driving a car. Therefore there is at least one x for which y will not drive a car.
forall x: P(x) -> ~Q(x). forall x: Q(x). exists x: R(x) -> P(x). forall x: P(x) -> R(x). Therefore exists x: ~R(x).