And a lot of people wonder how we rank more poorly in education than we should....
First of all, this is something so easy that you should know. Secondly, even if you don't know, there's this thing called google. Any intelligent person, who doesn't know something, would realize this. Just click on this link. It will take you step-by-step on how to use google:
http://lmgtfy.com/?q=What+was+the+Russian+revolution+in+1917