Draw the largest circle in the square. Given that the perimeter of the square is 36 centimeters, what is the area of the circle drawn in square centimeters?
在正方形里画一个最大的圆．已知这个正方形的周长是36厘米，画出的这个圆的面积是多少平方厘米．
<gadget id="calculator">36 / 4</gadget>
<output>9</output>

<gadget id="calculator">9 / 2</gadget>
<output>9/2 = around 4.5</output>

<gadget id="calculator">(9/2) ** 2</gadget>
<output>81/4 = around 20.25</output>

<gadget id="calculator">3.14 * (81/4)</gadget>
<output>63.585</output>

<result>63.585</result>