Why were shantytowns also called hoovervilles?

The british agricultural revolution resulted in many farmers losing their jobs. which sentence best explains the change that farmers experienced?

How was the method of making pottery by using coils of clay better than simply shaping the clay by hand? it prevented pottery from cracking when fired. it created a watertight seal. it produced more attractive pottery. the pottery could be cut or stamped with designs.

The rise of advertising in the 1920s. i am good with seeing how advertisements shape the roaring twenties and how it developed a new way of life through modern days. but i am not sure what the details of advertising in the 1920s were. if possible can you send me links (preferrably credential links) to sources that maybe show like the first company to start advertising through the radio, how advertising benefits (statistics graphs), etc.