How much does the surface area increase after sawing a cylindrical piece of wood with a length of 2 meters and a diameter of 4 decimeters at the bottom into 4 sections?
把一根长是2米，底面直径是4分米的圆柱形木料锯成4段后，表面积增加了多少．
<gadget id="calculator">4 / 2</gadget>
<output>2</output>

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

<gadget id="calculator">3.14 * 4</gadget>
<output>12.56</output>

<gadget id="calculator">12.56 * 6</gadget>
<output>75.36</output>

<result>75.36</result>