The math teacher cut the circle into an approximate rectangle. The length of the rectangle is 12.56 cm. What is the area of the original circle in square centimeters?
数学老师把圆剪拼成一个近似的长方形，长方形的长是12.56厘米，原来那个圆的面积是多少平方厘米．
<gadget id="calculator">12.56 / 3.14</gadget>
<output>4</output>

<gadget id="calculator">4 ** 2</gadget>
<output>16</output>

<gadget id="calculator">3.14 * 16</gadget>
<output>50.24</output>

<result>50.24</result>