The $CSA$ (Curved Surface Area) of a $1-$ rupee coin is given by the formula $\ldots \ldots \ldots \ldots .$

Write 'True' or 'False' and justify your answer:
An open metallic bucket is in the shape of a frustum of a cone,mounted on a hollow cylindrical base made of the same metallic sheet. The surface area of the metallic sheet used is equal to curved surface area of frustum of a cone + area of circular base + curved surface area of cylinder.

Three cubes of a metal whose edges are in the ratio $3:4:5$ are melted and converted into a single cube whose diagonal is $12\sqrt{3} \, \text{cm}$. Find the edges of the three cubes (in $\text{cm}$).

$A$ funnel (see figure) is the combination of

$A$ container is in the form of a cylinder closed at one end by a hemisphere. The radius of the cylinder is $8.4 \,cm$ and the total height of the container is $52.8 \,cm$. How many litres of petrol can this container hold? (in $litres$)

$TSA$ of a cone with radius $4\, cm$ and height $3\, cm$ is $\ldots \ldots \ldots \ldots cm^{2}$. (in $\pi$)