Which are characteristics of the aztec’s civilization?

Lloyd’s of london was one of the first institutions to offer insurance to merchants and joint-trade companies. a major part of the insurance system involved people who agreed to take responsibility for the insured losses in return for a fee. what were these risk-takers known as? a. joint-stock companies b. investors c. underwriters d. merchants e. capitalists

When did martin luther king, jr. deliver his famous "i have a dream" speech? a. during the montgomery bus boycott b. during the birmingham campaign c. during his acceptance of the nobel prize d. during the march on washington

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.