A cylindrical wood with a length of 4m, after cutting it into three sections, the surface area increases by 28dm**2, what is the original volume of this wood in m**3.
一根长4m的圆柱形木材，将它横截成三段后，表面积增加了28dm**2，这根木材原来的体积是多少m**3．
<gadget id="calculator">0.07 * 4</gadget>
<output>0.28</output>

<result>0.28</result>