How does trade and exchange affect groups of people? how does this relate to wealth in brazil?

Trade and exchange mostly always benefits those nations that engage to it, nevertheless only when it is average to the total national economy. Also, a minority is always hurt by the evolution of trade patterns, and they’ll always ask for protection. In relation with this, Brazil is composed of a only a few wealthy people and a lot of very poor people. This gap among the highest and lowest socials levels is so huge, even though it already decreased during the late 1990s. However, stabilization to the economy, by means of lower inflation levels has likely added more purchasing power to the less fortunate.

where are the statements?