How do I Identify and place on a map the key countries and alliances of WWI?

The u.s. constitution outlawed slavery. true false

Which of these effects of mass production techniques used during 1920

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.