What invention is most responsible for the expansion of enslaved labor in georgia?

Was the battle of iwo jima over after us troops raised the flag on mt. suribachi?

Explain the strengths of the articles of confederation and how people reacted to this document. ! ^^^ 10 points

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.