A cylindrical piece of wood is 2 meters long. After cutting it into two small cylinders, the surface area increases by 25.12 square decimeters. What is the original volume of this piece of wood?
一种圆柱形木材，长2米，把它截成两个小圆柱后，表面积比原来增加了25.12平方分米，原来这根木料的体积是多少？
<gadget id="calculator">25.12 / 2</gadget>
<output>12.56</output>

<gadget id="calculator">2 * 10</gadget>
<output>20</output>

<gadget id="calculator">12.56 * 20</gadget>
<output>251.2</output>

<result>251.2</result>