Answer: 81pi square meters
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Work Shown
C = 18pi is the given circumference
d = diameter which is unknown
C = pi*d
18pi = pi*d
18 = d
d = 18
The diameter is 18 meters.
Half of this is the radius r = d/2 = 18/2 = 9
The radius is 9 meters
Use the value of r to find the area of the circle
A = pi*r^2
A = pi*9^2
A = pi*81
A = 81pi
The area of the circular cross section is 81pi square meters