A cylinder with a height of 10 decimeters, if the height is reduced by 2 decimeters, the surface area will be reduced by 25.12 decimeters, what is the original volume of the cylinder in cubic decimeters?
一个高为10分米的圆柱，如果高降低2分米表面积就减少25.12平方分米，原来圆柱的体积是多少立方分米．
<gadget id="calculator">25.12 / 2 / 3.14 / 2</gadget>
<output>2</output>

<gadget id="calculator">2 ** 2</gadget>
<output>4</output>

<gadget id="calculator">3.14 * 4 * 10</gadget>
<output>125.6</output>

<result>125.6</result>