Answer:
=> The demographic future for the U.S. and the world looks very different than the recent past in key respects. Growth from 1950 to 2010 was rapid—the global population nearly tripled, and the U.S. population doubled. However, population growth from 2010 to 2050 is projected to be significantly slower and is expected to tilt strongly to the oldest age groups, both globally and in the U.S.
=> Aging is not exactly news—the U.S. and global populations also turned older from 1950 to 2010. But future prospects for aging have garnered more attention because, unlike in the past, younger populations, those of children and those of middle-age adults, are at near standstill. Thus, the social and economic effects of aging are likely to be felt more acutely in the future.
Explanation:

Self-Determination : a principle in modern International Law Which stated that nations has the right to choose their Sovereignity and Political Status
This Ideas Created several Countries after the Treaty of Versailles was signed such as Poland, Estonia, Latvia, and the separation of Serbia and Montenegro
A pretty cool history fair project would be the history of Halloween and it's origins since it's a most here...I'd be pretty cool