How many square meters of iron sheets are needed to make a cylindrical iron sheet chimney with ten sections 2 meters long and 8 cm in diameter?
做十节长2米，直径8厘米的圆柱形铁皮烟囱，需要铁皮多少平方米？
<gadget id="calculator">8 / 100</gadget>
<output>2/25 = around 0.08</output>

<gadget id="calculator">3.14 * (2/25) * 2 * 10</gadget>
<output>5.024</output>

<result>5.024</result>