The volume of the greatest sphere cut off from a circular cylindrical wood of base radius $1 \mathrm{cm}$ and height $6 \mathrm{cm}$ is

If a cone, a hemisphere and a cylinder have equal bases and have same height, then the ratio of their volumes is

A solid piece of iron in the form of a cuboid of dimensions $49 \mathrm{cm}\times 33 \mathrm{cm}\times 24 \mathrm{cm}$ is moulded to form a sphere. The radius of the sphere is