For a cylinder with a height of 10 cm, if its height is reduced by 2 cm, the surface area will be reduced by 25.12 cm2. Find the volume of the original cylinder.
一个高为10厘米的圆柱，把它的高减少2厘米，表面积就减少25.12平方厘米．求原来圆柱的体积．
<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>