What caused defoe's exile from england

As a result of the work of the house un-american activities committee, hundreds of people were

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.

Why did federalists fear the louisiana purchase? what did they think would happen?