Answer:
- Assasination of Arcduke.
- Secret alliances, internal politics, and the desire to grow empires had built up distrust and dislike between many of the European powers
- Austria-Hungary issued a number of harsh demands on Serbia, threatening to invade if Serbia did not comply. They gave them 48 hours to respond. When Serbia's response fell short of the demands, Austria-Hungary declared war on Serbia on July 28.
Step-by-step explanation:
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