Answer :
The formula to find circumference if you have diameter is:
pi multiplied by diameter.
So, 3.14*8= 25.12 cm
The circumference of the circle is 25.12 cm.
the formula for circumference is π×r×r (r=radius) to get the radius you do diameter÷2= , in this case the radius is 4cm π×4×4= 50.26cm circumference