1) Supported by many claims and was linked to including verified phone calls.

2) http://www.spiegel.de/international/world/russia-wary-of-nat...

http://articles.latimes.com/2014/mar/04/opinion/la-oe-walker...

http://www.forbes.com/sites/dougbandow/2016/09/22/say-no-to-...

3)>"Gifted" because Khrushchev's transfer was ostensibly to mark the 300th anniversary of Ukraine's merger with the Russian empire. And he probably didn't think the Soviet Union would be gone less than 40 years later.

http://www.npr.org/sections/parallels/2014/02/27/283481587/c...

4) 2/3 of Crimeans are ethnically Russian, and Russians have been the predominant people in Crimea for 100 years