Well theirs three business, technology, and culture <span />
Consumers spent more on improvised household appliances, automobile, and other goods manufactured through mass production.
<h3><u>Explanation:
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The boon that the United States economy receive in 1920's was majorly consumer centric. With the advent of new technologies, the spending habits of people changed as they got attracted towards the new and innovative commodities flooding the market.
Automobile was one such commodity. People, as a sign of dignity, bought cars that were newly being introduced into the market. They also started spending on new and improved domestic appliances as the notion of 'convenience of living' was on fleet during the 1920's.
OK so basically the main reason that had caused WWI was when the arch duke of Austria Hungary Franz Ferdinand was assassinated because the assassin had ties to a military group called the black hand so it had caused European powers to collide against each other.
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C. a representative government