Why did the Great Depression last so long?

 Please provide a comprehensive answer to the following two questions: 1) Which were the main causes of the Great Depression?  2) Why did the Great Depression last so long?   To answer these questions, please start with our textbook information and then use at least one more reputable source for your research.  Please use the bibliographic information recommended by the Modern Language Association (MLA).  Length: at least six pages, including bibliography.  For each question: write the question as a title and then provide your answers. TEXT BOOK: Gary M. Walton Hugh Rockoff. History of the American Economy. 12th Edition, 2014.