If a round wood with a base diameter of 4 cm and a height of 20 cm is divided into three cylinders of the same shape and size, how many square centimeters will the surface area increase compared to the original one?
一个底面直径是4厘米，高20厘米的圆住体木料，分成形状大小完全相同的三个圆柱体后，表面积比原来增加多少平方厘米．
<gadget id="calculator">4 / 2</gadget>
<output>2</output>

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

<gadget id="calculator">3.14 * 4 * 4</gadget>
<output>50.24</output>

<result>50.24</result>