Translate the following inference to logic notation: If David were bored, then Karen is driving a car. If Karen takes a plane, then David is bored. For all x, if x_10 drives a car, then x_10 is taking a plane. Therefore David is bored if and only if Karen is driving a car.
p -> P(a). Q(a) -> p. forall x: P(x) -> Q(x). Therefore p <-> P(a).