The Farmers' Alliance was originally formed to a break the economic grip of the railroads through farmers' cooperatives. b join poor black and white farmers in a political alliance to advance their similar economic interests. c drive up farm prices by reducing crop production. d undermine eastern bankers by providing low-cost loans to farmers. e advance agriculturally useful education in state land-grant colleges

a. break the economic grip of the railroads through farmers' cooperatives.

Explanation:

Farmers' Alliance was an American agrarian economic movement created by the farmers living and farming in the United States of America during the 1870s and 1880s. The Farmers' Alliance was aimed and focused on improving the economic conditions for all American farmers to grow, develop and flourish excellently through the establishment of cooperatives and political advocacy groups.

Furthermore, the Farmers' Alliance believed majority of the economic problem and challenges was caused by industrial monopolies, eastern bank and railroads.

Hence, the Farmers' Alliance was originally formed in order to break the economic grip considered to be caused by the railroads, through the establishment of farmers' cooperatives.

the first successful, urban blues recording, selling more than 75,000 copies, was made in year 1920.

mamie smith recorded the first commercially successful example of the urban blues,   with the recording of “crazy blues”."crazy blues" was recorded on august 10, 1920, in new york city. within a month of the release of “crazy blues” it had sold 75,000 copies.