Translate the following inference to logic notation: Elisabeth is not an electrician. If David drives a car, then Elisabeth is taking a plane. For all x, if x_17 takes a plane, then x_17 is an electrician. If Elisabeth were an electrician, then Elisabeth is taking a plane. If Joseph were a cashier, then David is driving a car. Therefore Joseph is not a cashier.
~P(a). p -> Q(a). forall x: Q(x) -> P(x). P(a) -> Q(a). q -> p. Therefore ~q.