The volume of a cone with radius $5 \, cm$ and height $21 \, cm$ is $\ldots \ldots \ldots \, cm^{3}$.

$A$ cylinder is closed at both the ends by $12 \, cm$ high cones. The radius of the cylinder is $5 \, cm$ and the total height of the combined article is $41 \, cm$. Find the total surface area of this article in $cm^2$. $(\pi = 3.14)$

The volume of a sphere with radius $1.5\,cm$ is $\ldots \ldots \ldots \ldots cm^{3}$. (in $\pi$)

For a cone,$l = \ldots \ldots \ldots \ldots$

Write 'True' or 'False' and justify your answer:
If a solid cone of base radius $r$ and height $h$ is placed over a solid cylinder having the same base radius and height as that of the cone,then the curved surface area of the shape is $\pi r \sqrt{h^{2} + r^{2}} + 2 \pi r h$.

........ litres of water at the most can be stored in a cubical tank with length $1\, m$.