A 10-meter-long iron wire is wound on a wooden stick with a circular cross-section, and 0.58 meters remain after 15 turns. What is the diameter of the cross-section of the stick?
一根10米长的铁丝，将它绕在一个横截面为圆形的木棍上，绕15圈后还剩下0.58米．木棍横截面的直径是多少米？
<gadget id="calculator">10 - 0.58</gadget>
<output>9.42</output>

<gadget id="calculator">9.42 / 15 / 3.14</gadget>
<output>0.2</output>

<result>0.2</result>