Translate the following inference to logic notation: For all x, y will cook if and only if y is a taxi driver. There is at least one x for which y will cook if and only if y is a sailor. Therefore there is at least one x for which if y were a taxi driver, then y is a sailor.
forall x: P(x) <-> Q(x). exists x: P(x) <-> R(x). Therefore exists x: Q(x) -> R(x).