Respuesta :

musiclover10045
if you know the diameter of the circle, multiply the diameter by PI

 if you know the radius of the circle multiply the radius by 2 then multiply by PI

Bladerunner1976
The circumference of a circle is as follows

given the Diameter: [tex]C= \pi *d[/tex]
given the radius: [tex]C=2* \pi *r[/tex]