Three chords of a sphere, each having length 5,6,7, intersect at a single point inside the sphere and are pairwise perpendicular. For R the minimum possible radius of the sphere, find R^{2}.
Three chords of a sphere, each having length 5,6,7, intersect at a single point inside the sphere and are pairwise perpendicular. For R the minimum possible radius of the sphere, find R^{2}.