Upton Sinclair, Frank Norris and Ida Tarbell made their greatest contributions to the Progressive movement by (4) publishing books and articles to expose the problems of society. Upton Sinclair wrote a book which showed the dangerous and unsanitary lives workers of the Meatpacking District went through on a daily basis, Frank Norris exposed the struggle railroad workers go through with their bosses and the unfairness of the railroad workers life in California and Ida Tarbell wrote about the manipulative men behind the oil trade.
Yeah what question do you need
The gravity of Jupiter helps the comets from hitting the earth
Banks loaned money to rich tycoons who were expanding the railroads