What invention allowed the british to know when attacks were coming

During the cold war, the united states was involved in certain regional conflicts due to fears later called the domino theory, which stated which concept?

Which british law required americans to house and feed british troops? sugar and molasses actstamp actnavigation actsquartering act

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.