I want to know the answer to the following question:
What years did Vladimir the Great reign as leader?
All the background I'm provided with is that "It is not clearly documented when the title of the Grand Duke was first introduced, but the importance of the Kiev principality was recognized after the death of Sviatoslav I in 972 and the ensuing struggle between Vladimir the Great and Yaropolk I.". Is that enough to answer the question?
Answer: no