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

$A$ hemispherical dome of a building needs to be painted. If the circumference of the base of the dome is $17.6 \, m$,find the cost of painting it,given the cost of painting is $Rs. 5$ per $100 \, cm^2$.

Find the amount of water displaced by a solid spherical ball of diameter $28 \, cm$.

The circumference of the base of a cylindrical vessel is $132 \,cm$ and its height is $25 \,cm$. How many litres of water can it hold (in $,l$)? $(1000 \,cm^3 = 1 \,l)$ Assume $\pi = \frac{22}{7}$.

Find the total surface area of a cone,if its slant height is $21 \, m$ and diameter of its base is $24 \, m$. (Take $\pi = \frac{22}{7}$) (in $, m^2$)

Twenty-seven solid iron spheres,each of radius $r$ and surface area $S$,are melted to form a single sphere with surface area $S^{\prime}$. Find the radius $r^{\prime}$ of the new sphere. (in $r$)