A small cylinder with a height of 1 cm is cut off from the top and bottom of a cylinder, and the surface area of the original cylinder is reduced by 25.12 square centimeters. What is the volume of the truncated cylinder in cubic centimeters?
在一个圆柱上端底面截去一个高为1厘米的小圆柱，原圆柱的表面积减少了25.12平方厘米．截去的小圆柱体积是多少立方厘米．
<gadget id="calculator">2 * 3.14 * 1</gadget>
<output>6.28</output>

<gadget id="calculator">25.12 / 6.28</gadget>
<output>4</output>

<gadget id="calculator">4 ** 2</gadget>
<output>16</output>

<gadget id="calculator">3.14 * 16 * 1</gadget>
<output>50.24</output>

<result>50.24</result>