What is the diameter of a sphere whose volume is 1410000000 cubic kilometers

I didn't have any luck with the on-site calculator in trying to calculate the radius.......it will give me the volume for a particular radius, but not vice-versa

So.......

1410000000  = (4/3)pi * r^3     

(1410000000 )/ (4pi/3)  = r^3      take the cube root of both sides

r = about 695.6 kilometers

Use this page on the formulary here: http://web2.0calc.com/formulary/math/geometry/sphere 

It will not only tell you the appropriate formula but also do the calculation for you (well, it will actually calculate radius for you, but then you can simply double the result to get diameter).

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