White families who moved into gentrified communities usually professed liberal attitudes toward people of color. therefore, gentrification failed to increase the dialogue between the new white residents and the former black residents because:

White families who moved into gentrified communities usually professed liberal attitudes toward people of color. Therefore, gentrification failed to increase the dialogue between the new white residents and the former black residents because of white residents' prejudices and discriminatory attitudes.

The word gentrification usually has a negative connotation. It refers to the displacement of the former residents by new members of the community. Former minority residents are forced to suffer a negative economic change and many times they are also the target of racial discrimination. The arrival of new residents results in a decline in the proportion of racial minorities and an increase in rents; therefore, former residents become more vulnerable. New white residents have a very different style of life, much wealthier than the racial minorities' lifestyle, and that is why gentrification has failed to increase the dialogue between these two groups.  

b) to encourage free trade

answer; product market;