A cuboid of wood is 1 meter long. When it is cut into two pieces, the surface area increases by 4 square decimeters. What is the volume of the cuboid?
一根长方体木料长1米，把它切成两段后，表面积增加了4平方分米，这个长方体的体积是多少．
<gadget id="calculator">4 / 2</gadget>
<output>2</output>

<gadget id="calculator">2 * 1 * 10</gadget>
<output>20</output>

<result>20</result>