Assume that the radius of the equator is r.Then by the formula of the circle's circumference,we have the expression
2pi ( r +250) as the circumference of the satellite,and 2 Pi r as the circumference of the equator.Then by taking the difference,we have 2*Pi*r + 500*Pi - 2*Pi*r = 500Pi,which is approximately 1570 miles.
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