Given that,
Mass of satellite = 500 kg
Gravitational force = 3000 N
We need to calculate the radius of the circular orbit
Using formula of gravitational force

Where, G = gravitational constant
R = radius of earth
h = radius of the circular orbit
M = mass of earth
m = mass of satellite
Put the value into the formula





(II). We need to calculate the speed of the satellite
Using formula of velocity

Put the value into the formula




(III). We need to calculate the period of the orbit
Using formula of time period

Put the value into the formula



Hence, (I). The radius of the circular orbit is 
(II). The speed of the satellite is 8.8 km/s.
(III). The period of the orbit is 1.00 hr.