"during the colonial era, the british promoted the policy of mercantilism to

It was to limit manufacturing in America.  The purpose of mercantilism was to restrict trading and business activities to the English crown.  Colonies could not sell their goods to other foreign countries nor were they allowed to trade on foreign vessels.  The British wanted to maximize the resources of the colonies for their own use.

answer; ///i believe that the correct answer is when the same ( isobar ) passes through two locations on a weather map,both locations have the same pressure;