Does anyone know how to do this ?

Work out the volume of the half of the sphere. Use the equation but you need to find the radius of the sphere. To do that fill in all the information you know to then work backwards and find the radius. That radius will be the same as for the sphere so use that to fill in your volume of the sphere, but remember to half that. Once you have found the volume of that half sphere add it onto the volume of the cone and that’s your final answer

Use a calculator basically