Translate the following inference to logic notation: For all x, if x_5 cooks, then x_5 is a musician. For all x, if x_5 were a musician, then x_5 is a sailor. For all x, x_5 will cook if and only if x_5 is a sailor. Therefore for all x, x_5 will cook if and only if x_5 is a sailor.
forall x: P(x) -> Q(x). forall x: Q(x) -> R(x). forall x: P(x) <-> R(x). Therefore forall x: P(x) <-> R(x).