cuboid piece of wood is 5m long. After sawing into two equal pieces, the surface area increases by 40c㎡. What is the volume of this piece of wood in dm**3.
一根长方体木料长5m，锯成相等的两段后，表面积增加了40c㎡，这根木料的体积是多少dm**3．
<gadget id="calculator">0.4 / 2</gadget>
<output>0.2</output>

<gadget id="calculator">5 * 10</gadget>
<output>50</output>

<gadget id="calculator">0.2 * 50</gadget>
<output>10</output>

<result>10</result>