Explain the significance of (a) New Mexico Territory, (b) William Becknell, (c) Santa Fe Trail, (d) Junipero Serra, (e) Manifest Destiny, (f) James K. Polk. please answer as many of these as you can it's due really soon

What is the main idea of this excerpt? 1.1.3

Powers of states the first letter of the answer is r.

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.