Grandma Wang surrounded a circular chicken coop. The diameter of this chicken coop is exactly the same as the perimeter of a square wooden board with a side length of 0.5 meters. What is the floor area of this chicken coop?
王奶奶围了一个圆形鸡舍，这个鸡舍的直径正好和一个边长是0.5米的正方形木板的周长相同，这个鸡舍的占地面积是多少？
<gadget id="calculator">4 / 2 / 3.14</gadget>
<output>0.636943</output>

<gadget id="calculator">0.5 * 0.636943</gadget>
<output>0.318472</output>

<gadget id="calculator">0.318472 ** 2</gadget>
<output>0.101424</output>

<gadget id="calculator">3.14 * 0.101424</gadget>
<output>0.318471</output>

<result>0.318471</result>