After cutting a 1-meter-long cylindrical steel into two sections, the surface area increases by 6.28 square decimeters. What is the original volume of this steel in cubic decimeters?
把一根长1米的圆柱形钢材截成2段后，表面积增加了6.28平方分米，这根钢材原来的体积是多少立方分米．
<gadget id="calculator">6.28 / 2</gadget>
<output>3.14</output>

<gadget id="calculator">3.14 * 1 * 10</gadget>
<output>31.4</output>

<result>31.4</result>