@Joshi, shreshtha :
To find the $9_{th}$ largest element -:
As the tree is balanced, the $9_{th}$ largest will be present at the rightmost subtree of height $9$.
i.e if array index is started from $1$ , then it is present at $ar[2^{8+1}-1]$ where h=height of tree..
hence finding $9_{th}$ largest cn be done in $O(1)$ ..isn't it ?