Whats the meaning of european expansion into africa left native regimes intact but has strong impact on local societies

How might the first nations have reacted when they saw that the europeans were moving onto their lands and disrupting their way of life? (this was when the europeans came to canada and tried to claim land to themselves)

Since so many american men during world war ii were fighting overseas, the factorices lay empty. this presented a problem the u. s. military was in such dire need of manufactured goods bullera, tanks, airplanes , ships, and many other things. whose point of view si best reflected in these lunes?

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.