After a section of cylindrical wood with a diameter of 10 cm is uncovered longitudinally along the diameter of the bottom surface, the surface area increases by 200 square centimeters. What is the original volume of this section in cubic centimeters?
把一段直径是10厘米的圆柱体木料沿底面直径纵向揭开以后，表面积增加了200平方厘米，原来这段的体积是多少立方厘米？
<gadget id="calculator">200 / 2 / 10 / 2</gadget>
<output>5</output>

<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

<gadget id="calculator">200 / 2 / 10</gadget>
<output>10</output>

<gadget id="calculator">3.14 * 25 * 10</gadget>
<output>785</output>

<result>785</result>