A round steel 20 cm long is divided into two parts of the same length, and the surface area is increased by 20 cm2, what is the volume of the original steel in cubic centimeters?
一根长20厘米的圆钢，分成一样长的两段，表面积增加20平方厘米，原钢材的体积是多少立方厘米．
<gadget id="calculator">20 / 2</gadget>
<output>10</output>

<gadget id="calculator">10 * 20</gadget>
<output>200</output>

<result>200</result>