I’m doing a test , there’s a time limit

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.

According to some historians which marks at the beginning of the us civil war

Which of the following resulted from asoka's rule of the mauryan empire? a. the empire gained control over india's southern trade routes. b. an order of secret police was developed to spy on people. c.alexander the great's troops left india. d. india experienced political unrest for many years.