A thin rope is to be trapped on a hockey stick. If the diameter of the stick is $4.9 \mathrm{cm}$ and has to be wrapped $250$ rounds, then length of rope needed$=\mathrm{\_\_\_\_\_} \mathrm{m}$

Distance of Moon from earth is approximately $384000 \mathrm{km}$. Find the circumference of the Moon's trajectory around the earth. It is circular.

Circumference of Equator is $40040 \mathrm{km}$. If $7000 \mathrm{km}$ above the surface of Earth a satellite revolves constantly then distance it has to cover to complete one revolution$=\mathrm{\_\_\_\_\_km}$