Find the surface area of a sphere of diameter $3.5\,m$ (in $m^2$).

$1 \text{ litre} = \ldots \ldots \ldots \text{ cm}^3$

The length,breadth,and height of a cuboidal box are $30 \, cm$,$20 \, cm$,and $8 \, cm$ respectively. Find the lateral surface area of the cuboidal box (in $cm^2$).

The radii of two cylinders are in the ratio of $2:3$ and their heights are in the ratio of $5:3$. The ratio of their volumes is

The length,breadth,and height of a metallic cuboid are $10\, cm$,$6\, cm$,and $4\, cm$ respectively. If the density of the metal is $7.8\, g/cm^3$,find the mass of the cuboid (in $g$).

The surface area of a sphere and the curved surface area of a hemisphere are equal. Find the ratio of their radii.