A square log 16 meters long is sawed into 5 equal sections, and the surface area is increased by 4 square meters. What is the volume of this square log?
把一根长16米的方木锯成相等的5段，表面积增加了4平方米，这根方木的体积是多少．
<gadget id="calculator">4 * 2</gadget>
<output>8</output>

<gadget id="calculator">4 / 8</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(1/2) * 16</gadget>
<output>8</output>

<result>8</result>