Divide a circle into several small sectors and put them together to form an approximate rectangle. The perimeter is 12 cm longer than the original one. What is the area of the circle in square centimeters?
把一个圆等分成若干个小扇形后拼成一个近似的长方形，周长比原来增加了12厘米，这个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>