The outer dimensions of a closed box are $12 \text{ cm}$ by $10 \text{ cm}$ by $8 \text{ cm}$. If the box is made of wood $1 \text{ cm}$ thick,find out the capacity of the box (in $\text{cm}^3$).

$3$ equal cubes are placed adjacently in a row. Find the ratio of the total surface area of the new cuboid to the sum of the surface areas of the three cubes.

$1496 \, cm^3$ 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 $cm$):

$A$ right circular cone is exactly fitted inside a cube in such a way that the edges of the base of the cone are touching the edges of one of the faces of the cube and the vertex is on the opposite face of the cube. If the volume of the cube is $343 \, c.c.$,then what approximately is the volume of the cone? (in $c.c.$)

$A$ $12\,m$ deep well with internal diameter $3.5\,m$ is dug. The earth taken out from it is spread evenly to form a platform of dimensions $10.5\,m \times 8.8\,m$. Determine the height of the platform in meters. (in $.25$)

If the diameter of a sphere is decreased by $25 \%$,its curved surface area will be decreased by (in $\%$).