n? n? . n?/4 n?/4 n?/2 n/16 n?/16 n?/16 n?/16 n2/4 Consider the recursion tree shown above for the recurrence T(n) = 2T(n/2) + n2. In this diagram, the amount of work done at each of the top three levels of the recursion tree is shown. How much work is done at the 4th level of the recursion tree - that is, the first level not shown in the diagram? Assume that n is a power of 2 for this question. O n^2 On^2/4 n^2/8 On^2/16