The slant height of a right circular cone is $10 \, m$,and its height is $8 \, m$. Find the area of its curved surface (in $\pi \, m^2$).

$A$ solid piece of iron of dimensions $49 \times 33 \times 24 \text{ cm}$ is moulded into a sphere. The radius of the sphere is......$\text{cm}$.

The radius of a cylinder is made twice as large. How should the height be changed so that its volume remains unchanged?

What is the length (in metre) of the longest rod that can be placed in a room which is $2$ $metre$ long,$2$ $metre$ broad,and $6$ $metre$ high?

$A$ field is in the form of a rectangle of length $18\, m$ and width $15\, m$. $A$ pit,$7.5\, m$ long,$6\, m$ broad and $0.8\, m$ deep,is dug in a corner of the field and the earth taken out is evenly spread over the remaining area of the field. The level of the field raised is......$cm$

$A$ 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 ₹).