Respuesta :

kiyagibbskg
r≈12.99 
c = Circumference=pid= 81.64 To find the radius of a circle you can just divide the diameter by 2. 
pi = 3.14 
d = diameter=c/3.14 Pi is always 3.14 or 22/7. 
d = 81.64/3.14 
d = 26 
r= radius= 26/2 
radius=13 cm