Translate the following inference to logic notation: For all x, x_9 will climb a mountain if and only if x_9 is an electrician. For all x, x_9 will not play squash. For all x, if x_9 plays squash, then x_9 is climbing a mountain. For all x, x_9 will play squash if and only if x_9 will climb a mountain. Therefore for all x, x_9 is not an electrician.
forall x: P(x) <-> Q(x). forall x: ~R(x). forall x: R(x) -> P(x). forall x: R(x) <-> P(x). Therefore forall x: ~Q(x).