How did this excerpt reflect the benefits and drawbacks of the magna carta

Who was william johnson? a. a revolutionary war veteran b. was the most prominent free black in mississippi c. a field slave d. inventor of the cotton gin

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.

How did southern slaveholders attempt to convince people in the north to support slavery?