Cut a cylinder with a circumference of 12.56 cm into several equal parts along the radius of the base and assemble it into an approximate cuboid. The surface area is increased by 20 cm2 compared to the original one. What is the volume of the original cylinder in cubic centimeters?
将一个底面周长为12.56厘米的圆柱体沿底面半径切成若干等份，拼成一个近似长方体，表面积比原来增加了20平方厘米，原来圆柱体的体积是多少立方厘米？
<gadget id="calculator">12.56 / 3.14 / 2</gadget>
<output>2</output>

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

<gadget id="calculator">20 / 2 / 2</gadget>
<output>5</output>

<gadget id="calculator">3.14 * 4 * 5</gadget>
<output>62.8</output>

<result>62.8</result>