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

Find the weight of a hollow cylindrical lead pipe $28\, cm$ long and $0.5\, cm$ thick. Its internal diameter is $8\, cm$. (in $kg$) (Weight of $1\, cm^3$ of lead is $11.4\, g$,$\pi = \frac{22}{7}$)

Find the diagonal of a cuboid whose dimensions are $12\, m$ by $10\, m$ by $8\, m$.

$A$ solid sphere of radius $1 \, cm$ is melted to convert into a wire of length $100 \, cm$. The radius of the wire (using $\sqrt{3} = 1.732$) is ......... $cm$.

If the volumes of two cubes are in the ratio $27: 1$,the ratio of their edges is

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...........$\pi\, cm^3$.