$3$ spherical balls of radii $1\, cm$,$2\, cm$,and $3\, cm$ are melted to form a single spherical ball. In the process,the loss of material is $25\%$. The radius of the new ball is.........$cm$.

How many bricks are required to build a $15\, m$ long,$3\, m$ high,and $50\, cm$ thick wall,if each brick measures $25\, cm \times 12\, cm \times 6\, cm$?

$A$ tent is in the shape of a right circular cylinder up to a height of $3\, m$ and then becomes a right circular cone with a maximum height of $13.5\, m$ above the ground. If the radius of the base is $14\, m$,find the cost of painting the inner side of the tent at the rate of ₹ $2$ per $m^2$ (in ₹).

$10$ identical solid spherical balls of radius $3 \text{ cm}$ are melted to form a single sphere. In this process,$20 \%$ of the solid is wasted. What is the radius (in $\text{cm}$) of the resulting sphere?

If the volume of a sphere is numerically equal to its surface area,then its diameter is ......... $cm$.

The volume of a right circular cone is $1232\, cm^3$ and its vertical height is $24\, cm$. Its curved surface area is.......$cm^2$.