What did the conquistadors conquer ?

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.

Experimented with communism before taking part in a number of civil rights and antiwar protest

The nile river is referred to as the giver and taker of life. explain what this means.