There is a rope with a length of 12.56m. Use this rope to enclose a square or a circle on the playground. Through calculation, which area is the largest?
有一根绳子长12.56m，用这根绳子在操场上围出一块正方形或圆的空地，通过计算，说明哪个面积最大？
<gadget id="calculator">12.56 / 4</gadget>
<output>3.14</output>

<gadget id="calculator">12.56 / 2 / 3.14</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">3.14 * 3.14</gadget>
<output>9.8596</output>

<gadget id="calculator">12.56 - 9.8596</gadget>
<output>2.7004</output>

<result>2.7004</result>