Can someone help me with this I need a answer ASAP

C: 62.8
If this helped please give thanks and maybe mark brainliest! Thanks!
Answer:
62.8 mm
Step-by-step explanation:
C= 2 X pi X r = 2 X pi X 10mm = 20 pi mm = around 62.8 mm
r = d/2 = 20mm/2 = 10mm