How do you make an anceit pyraimid out of something !

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

Which is the best example of a primary source ducument useful in the study of history ?

Plz how did the jews of the diaspora preserve their heritage?