$A$ right prism has a triangular base whose sides are $13\, cm, 20\, cm$ and $21\, cm$. If the altitude of the prism is $9\, cm$,then its volume is......$cm^3$

$A$ tent is in the shape of a right circular cylinder up to a height of $3\, m$ and then becomes a right circular cone with a maximum height of $13.5\, m$ above the ground. If the radius of the base is $14\, m$,find the cost of painting the inner side of the tent at the rate of ₹ $2$ per $m^2$ (in ₹).

The curved surface area of a right circular cone of height $15\, cm$ and base diameter $16\, cm$ is..........$\pi\, cm^2$.

$A$ solid sphere and a solid hemisphere have the same total surface area. The ratio of their volumes is

$A$ cylinder with base radius of $8\, cm$ and height of $2\, cm$ is melted to form a cone of height $6\, cm.$ The radius of the cone will be (in $cm$):

If a solid cone of volume $27\, \pi\, cm^3$ is kept inside a hollow cylinder whose radius and height are the same as that of the cone,then the volume of water needed to fill the empty space is...........$\pi\, cm^3$.