What is a concentration of a population of a city

What does it mean in the declaration of independence for cutting off our trade with all parts of the world

Select the five weaknesses of the articles of confederation. congress could not declare war or establish an army. congress could not levy taxes. congress could not control trade. not all the states were represented in congress. no national court system. no executive to enforce the laws. congress could not negotiate with foreign governments. the national government could not borrow money. nine of the states had to agree to pass a law.

Which describes a significant different between the north and the south in the year leading up to the civil war