Divide a cylindrical piece of wood with a length of 5 meters and a circumference of the base of 12.56 decimeters into two halves, find the surface area of each piece.
将一根长5米，底面周长12.56分米的圆柱形木料平均分成两半，求每根的表面积是多少．
<gadget id="calculator">12.56 / 3.14 / 2</gadget>
<output>2</output>

<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">5 * 5</gadget>
<output>25</output>

<gadget id="calculator">2 * 3.14 * 2 * 25</gadget>
<output>314</output>

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

<gadget id="calculator">3.14 * 4 * 2</gadget>
<output>25.12</output>

<gadget id="calculator">314 + 25.12</gadget>
<output>339.12</output>

<result>339.12</result>