2025 AHS PRELIMS P1 Q21

The cross-section of a piece of metal in the shape of a sector of a circle with centre \(O\) and radius \(20\text{ cm}\) is shown below. The piece of metal is \(50\text{ cm}\) thick. The volume of the piece of metal is \(2000\text{ cm}^3\).

1. Find angle \(POQ\) in radians.[2]
2. The piece of metal is melted and recast into a sphere. Find the radius of this sphere.[2]