$A$ small village, having a population of $5000$, requires $130\, \text{litres}$ of water per head per day. The village has an overhead cuboidal tank measuring $20\, \text{m} \times 13\, \text{m} \times 10\, \text{m}$. For how many days will the water of this tank last?

Find the surface area of a sphere of radius $50\, cm$ $(\pi = 3.14)$ (in $cm^2$).

Metal spheres,each of radius $2 \, cm$,are packed into a rectangular box of internal dimensions $16 \, cm \times 8 \, cm \times 8 \, cm$. When $16$ spheres are packed,the box is filled with preservative liquid. Find the volume of this liquid. Give your answer to the nearest integer. [Use $\pi = 3.14$] (in $cm^3$)

The height of a cone is $9 \, cm$. The area of the base is $1386 \, cm^2$. Find its volume (in $cm^3$).

The radii of two cylinders are in the ratio $3:2$ and their heights are in the ratio $8:11$. The ratio of their volumes is....... .

Find the curved surface area and the total surface area of a hemisphere with a radius of $17.5 \, cm$.