Translate the following inference to logic notation: Barbara is playing tennis if and only if Jessica is driving a car. For all x, if x_17 takes a plane, then x_17 is playing tennis. If Jessica drives a car, then Barbara is taking a plane. Therefore if Jessica drives a car, then Barbara is playing tennis.
P(a) <-> p. forall x: Q(x) -> P(x). p -> Q(a). Therefore p -> P(a).