Translate the following inference to logic notation: For all x, if x_13 climbs a mountain, then x_13 is driving a car. David is drinking water if and only if William is sad. David is not drinking water. For all x, if x_13 were sad, then x_13 is climbing a mountain. If William drives a car, then William is sad. Therefore William is not driving a car.
forall x: P(x) -> Q(x). p <-> R(a). ~p. forall x: R(x) -> P(x). Q(a) -> R(a). Therefore ~Q(a).