$A$ metallic sphere with radius $18 \,cm$ is melted and recast to produce cylinders with radius $3 \,cm$ and height $12 \,cm$. Find the number of cylinders produced.

$A$ cylindrical tank is closed at both the ends by cones of height $12 \, cm$. The diameter of the cylindrical part is $14 \, cm$ and its height is $20 \, cm$. Find the volume of this tank (in $cm^3$).

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

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

$1 \ m^{3} = \dots \dots \dots \text{ kilolitre}$

$A$ cylindrical tank with radius $8.4 \,cm$ is closed at one end by a hemisphere. If the total height of the tank is $52.8 \,cm$,how many litres of petrol can it contain (in $.088$)? (in $litres$)