help with (b) I had ended up with 7234.56

 

(b)       V_sphere  =  (4/3) π r³     

                         =  (4/3) • 3.1416 • 6³     

                         =  (4/3) • 3.1416 • 216     

                         =  904.78                      Guest, what you did wrong, you cubed the diameter instead of the radius.     

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