Respuesta :

The equation to find a circumference is
(c = circumference, r = radius, d = diameter)
c = 2r · π
So we need to find the radius. 

A radius is half of the diameter, so
12/2 = 6

Now put the value in the equation and solve. 
c = 2 · 6 · π
c = 12 · π
c = 37.7

The answer is 37.7

Hope this helped! If you have anymore questions or don't understand, please comment or DM me. :)
the answer would be 37.7