Height of satellite A above Earth's surface: hA=1.25RE Height of satellite B above Earth's surface: hB=19.25RE Hence, the orbital radii (distance from Earth's center): ‌rA=RE+hA=RE+1.25RE=2.25RE ‌rB=RE+hB=RE+19.25RE=20.25RE Formula for orbital speed For a satellite in a circular orbit around Earth: v=√‌
GME
r
where G is the gravitational constant and ME is Earth's mass. Thus, for two satellites A and B : ‌