Answer: The radius is 2 inches.
The circumference is approximately 12.56 inches.
Step-by-step explanation:
Given : The diameter of a dartboard = 4 inches
Since , radius is half of the diameter.
Therefore, radius of dartboard = (diameter) ÷ 2
= (4 inches ) ÷ 2 = 2 inches
Also, Formula for circumference : , where r is radius.
Now , Circumference of dartboard =
Hence, The radius is 2 inches.
The circumference is approximately 12.56 inches.