If a cylindrical piece of wood with a length of 3 meters is sawed into three sections, the surface area is increased by 12 square decimeters, what is the volume of this piece of wood in cubic decimeters?
把一跟长3米的圆柱形木料锯成三段，表面积增加12平方分米，原来这根木料的体积是多少立方分米？
<gadget id="calculator">3 - 1</gadget>
<output>2</output>

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

<gadget id="calculator">12 / 4</gadget>
<output>3</output>

<gadget id="calculator">3 * 3 * 10</gadget>
<output>90</output>

<result>90</result>