Question

What is the velocity of an Earth satellite that is in a circular orbit with a radius of 7.5 × 107 meters measured from the center of the Earth?

Answer 1

it's mass independent. balancing radial force and inertia:

\(F = \dfrac{GMm}{r^2} = \dfrac{mv^2}{r}\)

\( \dfrac{GM}{r} = v^2\)

and you can google G and M