I want to know the answer to the following question:
Including Arsenal, how many  teams  had won the Premier League up to 2013?
All the background I'm provided with is that "Arsenal had never progressed beyond the quarter-finals of the Champions League until 2005–06; in that season they became the first club from London in the competition's fifty-year history to reach the final, in which they were beaten 2–1 by Barcelona.". Is that enough to answer the question?
Answer: no