The earlybird communications satellite hovers over the same point on earth's equator indefinitely. this is because a. its orbital period is 24 hours b. it is beyond the main pull of gravity c. it pulls as hard on earth as earth pulls on it d. it is kept aloft by ground control e. forces other than earth's gravity act on it

The Earlybird ... and every TV satellite ... hovers over the same point
on Earth's equator indefinitely because its orbit is continually adjusted
to ...

-- be in the plane of the equator,

-- be as perfectly circular as possible,

-- have a period exactly equal to the Earth's rotation period ...
about 23 hours 56 minutes 4 seconds, not 24 hours. 

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