I need help ( just give me any answer that is true) What happened to Puerto Rico after gaining independence from Spain?

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.

According to article 1, why did massachusetts raise their taxes on citizens, and what about the currency of the time made it difficult for citizens to pay these taxes

Which of the following statements about the economic consequences of the civil war is not accurate. a. inflation caused prices to rise by 80% in the north. b. because southern farms cannot process enough food for everyone in the south the union navy allowed food shipments from britain. c. to pay for all of the food supplies and arrangements that were necessary for the union army congress instituted an income tax. d. business boomed in the north as factories and farms always had a market for their products.