Answer: Approximately 25.12 meters
This value is approximate because pi = 3.14 is approximate
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Work Shown:
r = 4 = radius
pi = 3.14 approximately
C = circumference
C = 2*pi*r
C = 2*3.14*4
C = 25.12
The circumference is approximately 25.12 meters.
Side note: The circumference is the same as the perimeter of a circle.