Translate the following inference to logic notation: For all x, x_11 is a carpenter if and only if x_11 is a mechanic. There is at least one x for which if x_11 were a carpenter, then x_11 is a server. For all x, if x_11 were a server, then x_11 is a mechanic. Therefore there is at least one x for which if x_11 were a carpenter, then x_11 is a mechanic.
forall x: P(x) <-> Q(x). exists x: P(x) -> R(x). forall x: R(x) -> Q(x). Therefore exists x: P(x) -> Q(x).