Translate the following inference to logic notation: For all x, if x_3 drives a car, then x_3 is a bartender. There is at least one x for which x_3 will drive a car or x_3 is not a bartender. Therefore there is at least one x for which x_3 will drive a car if and only if x_3 is a bartender.
forall x: P(x) -> Q(x). exists x: P(x) or ~Q(x). Therefore exists x: P(x) <-> Q(x).