A piece of round steel is 10m long, and now it is sawed into two small sections each 5m long, and the surface area is increased by 12.56㎡. Find the volume of this round bar.
一根圆钢长10m，现将它锯成每段长5m的两小段，表面积增加了12.56㎡．求这根圆钢的体积．
<gadget id="calculator">10 / 5</gadget>
<output>2</output>

<gadget id="calculator">12.56 / 2</gadget>
<output>6.28</output>

<gadget id="calculator">6.28 * 10</gadget>
<output>62.8</output>

<result>62.8</result>