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Hello Ken, The perimeter of a circle is given a different name, circumference. The formula for the circumference of a circle is, C = 2πr, where r is the radius. Thus we need to determine the radius of the lake. If the lake is 20 acres in area then converting we get 80937 square meters. The formula for the area of a circle is A = πr^{2 }so we have
Plugging into the circumference formula yields,
Tyler  


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