$A$ 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.

How many cubic centimetres of iron are required to construct an open box whose external dimensions are $36 \, cm$,$25 \, cm$,and $16.5 \, cm$,provided the thickness of the iron is $1.5 \, cm$? If one cubic $cm$ of iron weighs $7.5 \, g$,find the weight of the box.

$A$ metallic sphere with radius $6 \, cm$ is melted and recast into a wire of radius $0.4 \, cm$. Find the length of the wire in metres.

$A$ cone of radius $8 \, cm$ and height $12 \, cm$ is divided into two parts by a plane through the mid-point of its axis parallel to its base. Find the ratio of the volumes of the two parts.

$A$ solid toy is in the form of a hemisphere surmounted by a right circular cone. The height of the cone is $2 \, cm$ and the diameter of the base is $4 \, cm$. Determine the volume of the toy. If a right circular cylinder circumscribes the toy,find the difference of the volumes of the cylinder and the toy. (in $cm^3$) (Take $\pi = 3.14$)

The volume of a cone with radius $5 \, cm$ and height $12 \, cm$ is ........ $\pi \, cm^{3}$.