Respuesta :

The formula is 2pi(radius) so 13*2*pi=26pi

so there are two formulas C= [tex] \pi [/tex]d and C=2[tex] \pi [/tex]r
we are going to use C=2 pi r
so since the radius is 13 we do 13×2×3.14, which equals to 81.64
So the circumference is 81.64 centimeters.