A 2-meter-long cuboid steel plate is cut into 5 cuboids, and the surface area increases by 40 square decimeters. What is the volume of this steel plate?
一段长2米的长方体钢板，将它截成5段长方体，表面积增加了40平方分米，这块钢板的体积是多少平方分米？
<gadget id="calculator">5 - 1</gadget>
<output>4</output>

<gadget id="calculator">4 * 2</gadget>
<output>8</output>

<gadget id="calculator">40 / 8</gadget>
<output>5</output>

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

<gadget id="calculator">5 * 20</gadget>
<output>100</output>

<result>100</result>