13. following the breakup of the soviet union, 15 of its former republics became independent. twelve of these former republics formed the commonwealth of independent states, largely in recognition of a. the economic threat posed by the european union. b. common cultural ties. c. the threat posed by nato. d. the need to sustain the trade flows established during soviet times.

I don't think that the Commonwealth was actually threatened by the NATO and the EU. While they did have cultural ties, they did not need this organization to keep them. I think that the best answer is the following one: D. the need to sustain the trade flows established during Soviet times.

The investiture controversy began as a power struggle between pope gregory vii (1072–85) and henry iv, holy roman emperor (1056–1106).[2] a brief but significant struggle over investiture also occurred between henry i of england and pope paschal ii in the years 1103 to 1107, and the issue played a minor role in the struggles between church and state in france, as well.by undercutting the imperial power established by the salian emperors, the controversy led to nearly 50 years of civil war in germany, and the triumph of the great dukes and abbots. imperial power was finally re-established under the hohenstaufen dynasty. historian norman cantor:

980 is the correct answer