Balboa: what was the columbian exchange?

How did the roaring 20s mark the end of the progressive era? a. mass production reduced wealth disparity and turned public opinion pro business b. labor unions won big legislative gains in workers rights and disbanded c. public officials cut taxes on businesses and reduced spending on services d. america increasing influence in world affairs redirected public attention to foreign policy

Interest groups are protected by the first amendment guarantees of petition and what other freedom?

What was herbert hoover and the food administration do in wwi?