Cut a circular piece of paper into several equal parts along the radius, and assemble it into an approximate rectangle. The circumference of this rectangle is 12 cm longer than the circumference of the circle. What is the area of the circle in square centimeters?
把一张圆形纸片，沿半径剪成若干等份，拼成一个近似的长方形，这个长方形的周长比圆的周长长12厘米，该圆的面积是多少平方厘米．
<gadget id="calculator">12 / 2</gadget>
<output>6</output>

<gadget id="calculator">6 ** 2</gadget>
<output>36</output>

<gadget id="calculator">3.14 * 36</gadget>
<output>113.04</output>

<result>113.04</result>