If the radius of a circular square with a circumference of 31.4m is widened by 1m, how many square meters will the area increase?
把一块周长是31.4m的圆形广场的半径扩宽1m，面积增加多少平方米？
<gadget id="calculator">3.14 * 225</gadget>
<output>706.5</output>

<gadget id="calculator">31.4 / 3.14 / 2</gadget>
<output>5</output>

<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

<gadget id="calculator">3.14 * 25</gadget>
<output>78.5</output>

<gadget id="calculator">706.5 - 78.5</gadget>
<output>628</output>

<result>628</result>