Answer:
Diameter = 16 cm
Circumference = 16π cm
Explanation:
History behind Diameter and radius
Diameter is the distance between one edge of the circle to the opposite edge where it cuts through the center of mass. Radius is half the diameter spanning the center to the edge.
This being said your diameter is twice your radius.
The circumference is πd, which is the same as 2πr, because multiplication dont care which order.
So your radius is 8 cm that means your diameter is 8 x 2 which is 16 cm.
Now to make it quick we can multiply that by pi to get our circumference.
16π ≅ 16(3.141) ≅ 50.256 cm
Hope this helps,