Who exposed the plight of the urban poor in 1889's "how the other half lives"?

The one responsible of exposing the plight of the urban poor in 1889’s. “How the other half lives” is Jacob Riis. He is a reformer and a reporter that is responsible of creating the book, “How The Other Half Lives” in which had shock its readers because of the factual information that they have provided.

25. twelve tables

26. having important positions chosen by lot

worldwide, 780 million people do not have access to an improved water source. an estimated 2.5 billion people lack access to improved sanitation (more than 35% of the world's population)