A solid sphere and a hollow sphere of same material are floating in a liquid. Radius of both spheres are same, percentage of volume immersed of both the spheres will be same.

Upthrust acts on volume of liquid displaced. It has nothing to do whether the body is solid or hollow. But percentage of volume of solid sphere immersed is not same as percentage of volume of hollow sphere immersed because both solid & hollow spheres have same volume & made of same material but mass of solid sphere > mass of hollow sphere.

So here we get A is false but R is true