I believe the answer is: <span>prisoners and guards
The purpose of study is to find out how human would behave when given complete authrority towards other humans.
As it turned out, the participants who were assigned as guards started to use their power to abuse the participants who were assigned as prisoners, and researchers were forced to stop the experiment.</span>
This timeline shows the leaders of the Soviet Union and when they ruled starting with Kerensky, the head of the Provisional Government, and ending with Gorbachev in 1991 when the Russian Republic was formed. http://www.rff.com/timeline_soviet.htm
