On teacher's day this year, Xiao Hong made a semicircle for her teacher with colored cardboard. In order to make it beautiful, he bought colored rope to glue it to the outside of the card, It took 41012cm long colored rope to make this card. How many square centimeters of colored cardboard did he use? The content is clear, neat and clear Wrong! It's 41.12cm

Radius: 41.12 △ 2 + 3.14 = 41.12 △ 5.14 = 8cm
Area: 8x8x3.14x1/2 = 100.48 square centimeter
A: 100.48 square centimeters
Ha ha, I will do it in the future_ ∩)O

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