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You are a multimedia mogul who wants to launch your own
broadband communications satellite.  You want it to stay above
Kansas at all times - in other words, you want it to achieve a
geostationary orbit.  This means each orbit should take 24 hours.
You know that at an orbital distance of 6660 km from Earth's center,
a satellite takes 90 minutes to make one orbit.

   (a) What is the difference between applying Kepler's Third Law
       to satellites around Earth and applying it to
       planets around the Sun?
   (b) How many times longer is 24 hours than 90 minutes?
   (c) Using Kepler's Third Law, compute the orbital distance from
       Earth's center to send your broadband satellite.