If the radius of a sphere is doubled,its volume becomes $\ldots \ldots \ldots \ldots$ times the original volume.

........ litres of water at the most can be stored in a cubical tank with length $1\, m$.

How many cones with diameter $7\,cm$ and height $3\,cm$ can be produced by melting a metallic sphere with diameter $21\,cm$?

$A$ cylinder is closed at both the ends by hemispheres. The radius of the cylinder is $4.2 \, cm$ and the total height of the solid is $15 \, cm$. Find the volume of this solid (in $cm^3$).

The radius of a cone is $15 \, cm$ and its base is hemispherical. If the total height of the solid is $55 \, cm$,find its volume in $cm^3$.

$A$ solid iron cuboidal block of dimensions $4.4 \, m \times 2.6 \, m \times 1 \, m$ is recast into a hollow cylindrical pipe of internal radius $30 \, cm$ and thickness $5 \, cm$. Find the length of the pipe in meters.