If you know that the exact volume of a cylinder is 500 π cm3, how can you find the approximate volume, without knowing the height or radius of the cylinder? answer in a full sentence, and then calculate the approximate volume.

Question is very vague, I'll give it a try.

If we know the exact volume, to be V=500 π , this means that an approximate value pi is intended.

The following are approximate values of pi
π = 3, V=1500 cm^3  (1 significant figure)
π = 3.1, V=1550 cm^3 (2 significant figures)  
π = 3.14, V=1570 cm^3 (3 significant figures)   
π = 3.14, V=1570 cm^3 (3 significant figures)   
π = 22/7, V=1571 cm^3 (3 significant figures)   
π = 355/113, V=1570.796 cm^3 (7 significant figures) 
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