If a log with a length of 5 meters and a cross-sectional diameter of 6 decimeters is cut into two pieces, how many square decimeters will the surface area increase?
把一段长5米横截面直径为6分米的圆木，截成两段后，表面积增加了多少平方分米
<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">3 ** 2</gadget>
<output>9</output>

<gadget id="calculator">3.14 * 9 * 2</gadget>
<output>56.52</output>

<result>56.52</result>