HI

The gravitational attraction between the satelite and the earth is the same as the centripetal force of the satelite so

Let M be the mass of earth and small m be the mass of satelite .

Note that omega=2pi/T

Rearranging ..

Now you know R , H , G (Gravitational constant) , Mass of the earth is not given but you can check it out in your book since i hv forgotten .

Then substitute .