Translate the following inference to logic notation: For all x, z will not play tennis. There is at least one x for which z will play tennis or z is not a mechanic. For all x, if z plays tennis, then z is a mechanic. Therefore there is at least one x for which z is not a mechanic.
forall x: ~P(x). exists x: P(x) or ~Q(x). forall x: P(x) -> Q(x). Therefore exists x: ~Q(x).