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