In this task, you're given an open-domain question. Your task is to provide an answer to the given question. There is only one unique answer for each question. Your answer should be short, and refer to an entity, date, number, etc. Do not put your answer in the context of a sentence.

When was the last time the us constitution changed?
May 5, 1992

Who did oprah winfrey play in the color purple?
Sofia

What country dominated eastern europe after world war ii?

Soviet Union