$A$ metal pipe is $77 \,cm$ long. The inner diameter of a cross section is $4 \,cm$ and the outer diameter is $4.4 \,cm$. Find its outer curved surface area. (in $,cm^{2}$)

It costs $Rs. 2200$ to paint the inner curved surface of a cylindrical vessel $10\, m$ deep. If the cost of painting is at the rate of $Rs. 20$ per $m^2$,find the capacity of the vessel. (in $, kl$)

$A$ capsule of medicine is in the shape of a sphere of diameter $3.5 \, mm$. How much medicine (in $mm^3$) is needed to fill this capsule (in $, mm^3$)?

What length of tarpaulin $3\, m$ wide will be required to make a conical tent of height $8\, m$ and base radius $6\, m$ (in $, m$)? Assume that the extra length of material that will be required for stitching margins and wastage in cutting is approximately $20\, cm$ (Use $\pi = 3.14$).

Find the surface area of a sphere of diameter $14 \, cm$.
Assume $\pi = \frac{22}{7}$. (in $, cm^2$)

Find $(i)$ the curved surface area and $(ii)$ the total surface area of a hemisphere of radius $21\, cm$.