Divide a circle into several parts and cut them into an approximate rectangle. It is known that the perimeter of the rectangle is 12.42 centimeters. What is the area of the circle in square centimeters?
把一个圆平均分成若干份后剪拼成一个近似的长方形，已知拼成的长方形周长是12.42厘米，这个圆的面积是多少平方厘米．
<gadget id="calculator">3.14 * 2</gadget>
<output>6.28</output>

<gadget id="calculator">6.28 + 2</gadget>
<output>8.28</output>

<gadget id="calculator">12.42 / 8.28</gadget>
<output>1.5</output>

<gadget id="calculator">1.5 ** 2</gadget>
<output>2.25</output>

<gadget id="calculator">3.14 * 2.25</gadget>
<output>7.065</output>

<result>7.065</result>