The [Roman] envoy when he comes to the frontier of the offending nation . . . says: Hear, O Jupiter, and hear ye lands [i. e., of such and such a nation], let Justice hear! I am a public messenger of the Roman people. Justly and religiously I come, and let my words bear credit! Then he makes his demands, and follows with a solemn appeal to Jupiter. If I demand unjustly and impiously that these men and goods be given to me, the herald of the Roman people, then suffer me never to enjoy again my native country! These words he repeats when he crosses the frontiers; he says them also to the first man he meets [on the way]; again when he passes the gate; again on entering the [foreigners'] market-place. . . . If the persons he demands are not surrendered after thirty days, he declares war. — Livy, The Roman Way of Declaring War What is the first thing the Romans must do to declare war? a. attack the frontier b. make a public announcement c. attack the marketplace d. consult the rulers of Rome