How many square decimeters of iron sheets are needed to make 10 cylindrical sewer pipes with a length of 1 meter and a bottom radius of 6 cm.
做10节长1米，底面半径6厘米的圆柱形下水管，至少需要多少平方分米的铁皮．
<gadget id="calculator">1 * 100</gadget>
<output>100</output>

<gadget id="calculator">10 / 100</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">3.14 * 2 * 6 * 100 * (1/10)</gadget>
<output>376.8</output>

<result>376.8</result>