The land run by lords/ barons, worked by peasants & serfs, protected by the vassals

answer: karl marx, max weber, and emile durkheim (the fourth could be considered georg simmel)

explanation:

roosevelt, a progressive reformer, earned a reputation as a "trust buster" through his regulatory reforms and anti-trust prosecutions. his "square deal" included regulation of railroad rates and pure foods and drugs; he saw it as a fair deal for both the average citizen and the businessmen.

industrial revolution, in modern history, the process of change from an agrarian and handicraft economy to one dominated by industry and machine manufacturing