Total surface area of a closed cube with length $4 \, cm$ is $\ldots \ldots \ldots cm^{2}$.

The curved surface area of a cone with radius $12 \, cm$ and slant height $20 \, cm$ is ....... $\pi \, cm^2$.

$A$ top is made by joining a hemisphere to the base of a cone. The radius and the height of the conical part are $2.8 \, cm$ and $6.4 \, cm$ respectively. Find the volume of the top in $cm^3$.

$A$ cylindrical tank is closed at both the ends by hemispheres. Its radius is $2.1 \,m$ and the total height is $9.2 \,m$. How many litres of petrol can it contain?

Which of the following correctly matches the information given in Part $I$ and Part $II$?

Part $I$	Part $II$
$1.$ Volume of a cuboid	$a.$ $\frac{1}{3} \pi r^{2} h$
$2.$ Volume of a cone	$b.$ $\pi r^{2} h$
$3.$ Volume of a cylinder	$c.$ $\frac{4}{3} \pi r^{3}$
$4.$ Volume of a sphere	$d.$ $lbh$

$A$ cylinder is closed at both the ends by hemispheres. The radius of the cylinder is $20 \, cm$ and the total height of the article is $80 \, cm$. Find the total surface area of this combined article. $(\pi = 3.14)$ (in $cm^2$)