Pleaseeeew HELPPPP no one ever answers my questions on here

Answer:
Circumfrence: 40.21
Radius: 6.4
Step-by-step explanation:
For radius, you only have to divide the diameter (in this case 12.8) by 2 which gives us 6.4
For Circumference, plug in the radius in the formula C=2π(6.4), and that gives us 40.21