Why did the partition of africa create artificial boundaries

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.

What happened during the victorian age? a. all social classes lived near each other b. the middle class became much larger c. city populations began to decrease d. families continued to go to work together

How did cowboy culture reflect the ethnic diversity of the u.s.