Why did African Americans begin developing their own businesses in North Carolina's cities? to take control of the city's economy
to have easier access to services such as loans and insurance
to establish a system of common ownership
to force the city's white-owned businesses to close

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.