Hi, can someone please explain how to do this question?

I'm not just looking for an answer, as I would very much appreciate knowing how to do it too. I'm not even sure I know what an integer or an index is yet.Quote:

Write the number http://learn.open.ac.uk/filter/mathm...afd3c198090e32 as a power of 4. What is the value of the index?

Give your answer as an integer.