Translate the following inference to logic notation: For all x, if y were a musician, then y is a cashier. For all x, if y were a musician, then y is a cashier. For all x, if y were a cashier, then y is a musician. Therefore for all x, y is a cashier if and only if y is a musician.
forall x: P(x) -> Q(x). forall x: P(x) -> Q(x). forall x: Q(x) -> P(x). Therefore forall x: Q(x) <-> P(x).