There is a circular iron plate with a square cut out in the middle. The area of the square is 8 square centimeters. The radius of the circle is exactly the side length of the square. How many square centimeters is the area of the circle larger than the square?
有一个圆形铁片，中间挖去一个正方形，正方形的面积是8平方厘米，圆的半径恰好是正方形的边长，圆的面积比正方形大多少平方厘米．
<gadget id="calculator">3.14 * 8</gadget>
<output>25.12</output>

<gadget id="calculator">25.12 - 8</gadget>
<output>17.12</output>

<result>17.12</result>