Which lasting document, written in 1215 limits the power of rulers and was used by the colonists’ has an example of what government in america should be based on?

The Magna Carta was a charter issued by King John of England. The king was facing rebellion from the common folk because of his arrogance, thinking he was above the law. By signing the Magna Carta, it marked the first time a monarch was acknowledging a limit on his or her power. The Magna Carta stated that no one, not even the king was above the law, and that everyone is guaranteed the right to justice and to a fair trial. 

high entry costs prevent new producers from entering the market.

explanation:

an oligopoly is a term used to clarify the structure of a particular market, industry, or organization. a market is considered oligopolistic or amazingly focused when it is shared between a few companies.