$A$ right prism has a triangular base whose sides are $13\, cm, 20\, cm$ and $21\, cm$. If the altitude of the prism is $9\, cm$,then its volume is......$cm^3$

$A$ cylinder with base radius $8\, cm$ and height $2\, cm$ is melted to form a cone of height $6\, cm$. The radius of the cone will be (in $cm$):

$A$ right cylinder and a right circular cone have the same radius and the same volume. The ratio of the height of the cylinder to that of the cone is

$A$ rectangular block of metal has dimensions $21\, cm$, $77\, cm$, and $24\, cm$. The block is melted into a sphere. The radius of the sphere is .......... $cm$. (Take $\pi = \frac{22}{7}$)

$A$ hollow sphere of internal and external diameters $4\,cm$ and $8\,cm$ respectively is melted into a cone of base diameter $8\,cm$. The height of the cone is......$cm$.

$1496 \, cm^3$ of a metal is used to cast a pipe of length $28 \, cm$. If the internal radius of the pipe is $8 \, cm$,then the outer radius of the pipe is (in $cm$):