Answer: D) 628 m^2
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Explanation:
Let's find the area of the full circle first. The radius is 20 meters, since that's half of the diameter 40. So we have r = 20.
We'll use pi = 3.14 as an approximation
A = area of full circle
A = pi*r^2
A = 3.14*20^2
A = 1256
This is the area of a full circle, but we want half of that because we want the area of a semicircle instead. Since your teacher put 1256 for choice C in there, it seems like that is a trick answer.
We'll divide 1256 over 2 to get 1256/2 = 628 square meters as the final answer, which is choice D.
We can abbreviate "square meters" into "m^2".
