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3) given that the diameter of the semicircles is 40 yards each, you multiply it by pi to get approximately 125.66 yards. Now you have to divide it in half, since it’s a semicircle. Your final answer is approximately 62.83 yards.
4) to start this question, we head back to our 125.66 yard answer, since two semicircles equal a circle. 125.66 + 100 + 100 = 325.66, which is our final answer.