$A$ metallic cone with radius $5 \, cm$ and height $8 \, cm$ is melted and recast to produce identical balls with diameter $0.5 \, cm$. Find the number of balls produced.

$A$ drinking glass in the shape of a frustum of a cone has radii $3\,cm$ and $2\,cm$. If its height is $21\,cm$,its capacity is $\ldots \ldots \ldots cm^{3}$.

$16$ glass spheres,each of radius $2 \,cm$,are packed into a cuboidal box of internal dimensions $16 \,cm \times 8 \,cm \times 8 \,cm$. The box is then filled with water. Find the volume of water filled in the box (in $cm^3$).

The base of a cone with radius $15 \, cm$ and slant height $25 \, cm$ is hemispherical. Find the volume of this solid. $(\pi = 3.14)$ (in $cm^3$)

The capacity of a cylindrical tank with radius $1.4 \, m$ and height $4 \, m$ is $\ldots \ldots \ldots$ litres.

$A$ metallic sphere of radius $6 \, cm$ is melted and recast into a wire with diameter $1 \, cm$. Find the length of the wire in metres.