Translate the following inference to logic notation: For all x, x_7 is not a doctor. There is at least one x for which if x_7 were an office clerk, then x_7 is playing tennis. For all x, if x_7 were an office clerk, then x_7 is a doctor. For all x, if x_7 plays tennis, then x_7 is an office clerk. For all x, if x_7 were a doctor, then x_7 is an office clerk. Therefore there is at least one x for which x_7 will not play tennis.
forall x: ~P(x). exists x: Q(x) -> R(x). forall x: Q(x) -> P(x). forall x: R(x) -> Q(x). forall x: P(x) -> Q(x). Therefore exists x: ~R(x).