Translate the following inference to logic notation: Charles is taking a plane if and only if Richard is a server. For all x, y is not a writer. For all x, if y were a server, then y is a writer. For all x, if y were a writer, then y is a server. Therefore Charles is not taking a plane.
p <-> P(a). forall x: ~Q(x). forall x: P(x) -> Q(x). forall x: Q(x) -> P(x). Therefore ~p.