piece of cylindrical wood with a length of 2 meters, after cutting off a piece of cylindrical wood with a thickness of 0.4 meters from one end, the surface area of the log is reduced by 1.256 square meters. What is the surface area of the original wood in square meters?
一段长2米的圆柱形木料，从一端截去0.4米厚的一段圆柱木料后，原木料的表面积减少1.256平方米．原来木料的表面积是多少平方米？
<gadget id="calculator">1.256 / 0.4</gadget>
<output>3.14</output>

<gadget id="calculator">3.14 * 2</gadget>
<output>6.28</output>

<gadget id="calculator">3.14 / 3.14 / 2</gadget>
<output>0.5</output>

<gadget id="calculator">0.5 ** 2</gadget>
<output>0.25</output>

<gadget id="calculator">3.14 * 0.25 * 2</gadget>
<output>1.57</output>

<gadget id="calculator">6.28 + 1.57</gadget>
<output>7.85</output>

<result>7.85</result>