Cut a cylindrical piece of wood into 3 sections, the surface area increases by 12.56 square decimeters, what is the area of the bottom of this piece of wood in square decimeters?
把一根圆柱木料截成3段，表面积增加了12.56平方分米，这根木料的底面积是多少平方分米．
<gadget id="calculator">12.56 / 4</gadget>
<output>3.14</output>

<result>3.14</result>