Which statement about the technology developed during world war 1 is correct ?

How did settlers decide where to live ?

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.

During world war ii, which battle was the first significant us victory in the pacific?