Translate the following inference to logic notation: For all x, if x_4 were an astronaut, then x_4 is a sailor. For all x, if x_4 were a server, then x_4 is an astronaut. For all x, if x_4 were a sailor, then x_4 is a server. Therefore if Robert were a sailor, then Robert is a server.
forall x: P(x) -> Q(x). forall x: R(x) -> P(x). forall x: Q(x) -> R(x). Therefore Q(a) -> R(a).