Translate the following inference to logic notation: For all x, x_10 is a server if and only if x_10 is rich. For all x, if x_10 were a server, then x_10 is rich. For all x, if x_10 were a server, then x_10 is reading a book. For all x, if x_10 reads a book, then x_10 is rich. Therefore for all x, x_10 is a server if and only if x_10 is rich.
forall x: P(x) <-> Q(x). forall x: P(x) -> Q(x). forall x: P(x) -> R(x). forall x: R(x) -> Q(x). Therefore forall x: P(x) <-> Q(x).