A disc of radius R and thickness \(\frac{R}{6}\) has moment of inertia I about an axis passing through its centre and perpendicular to its plane. Dise is melted and recast into a solid sphere. The moment of inertia of a sphere about its diameter is
1
\(\frac{1}{5}\)
2
\(\frac{1}{6}\)
3
\(\frac{1}{32}\)
4
\(\frac{1}{64}\)