Which body of the UN probably knows the most about the work of all UN agencies?

Which of the following two groups did not do battle with the romans? select all that apply.

What event caused germany’s economy to fail?

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.