r = c/2pi (radius of a circle equals the circumference divided by (2 x pi)
radius = diameter divided by two
3.14
The tennis ball. But do you know why? The anser to that is in the relationship between the fomula for a shere's volum and that of it's surface area. Area is a radius squared function whereas volume is a radius cubed function.
BaO
Water is H2O
NaOH
CH3COOK
NH3
CO
Water is H2O
CaSO4
[NH4]+