Translate the following inference to logic notation: For all x, x_7 is an artist or x_7 is an astronaut. For all x, x_7 is an artist if and only if x_7 will play tennis. For all x, if x_7 plays tennis, then x_7 is a politician. For all x, if x_7 were an astronaut, then x_7 is playing tennis. Therefore for all x, x_7 is a politician.
forall x: P(x) or Q(x). forall x: P(x) <-> R(x). forall x: R(x) -> S(x). forall x: Q(x) -> R(x). Therefore forall x: S(x).