Master Wang makes 10 sections of cylindrical ventilation pipes of the same size, each section is 80 cm long, and the radius of the bottom surface is 5 decimeters. How many square meters of iron sheet will be used in total?
王师傅做10节同样大小的圆柱形通风管，每节长80厘米，底面半径是5分米，一共要用多少平方米的铁皮？
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