A circular plot is watered by a sprinkler that rotates through it. The sprinkler only rotates through a semi-circle, or half of the whole circle.
Area of a circle: A = pi x r^2
r = 160 / 2 = 80
A = pi x 80^2
A = 6400pi / 2 = 3200pi
3200pi = 10053.0965
The area water is approximately 10,053 ft^2.
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