A cylindrical ventilation pipe has a bottom diameter of 10 cm and a length of 1 meter. How many square decimeters are needed to make 10 such ventilation pipes?
一种圆柱形通风管的底面直径是10厘米，长1米，做10根这样的通风管至少需要多少平方分米．
<gadget id="calculator">10 / 10</gadget>
<output>1</output>

<gadget id="calculator">3.14 * 1 * 1 * 10 * 1 * 10</gadget>
<output>314</output>

<result>314</result>