If the circumference of a circle increases by 20%, how much does the area of the circle increase?
一个圆的周长增加20%，这个圆的面积增加多少．
<gadget id="calculator">1 ** 2</gadget>
<output>1</output>

<gadget id="calculator">3.14 * 1</gadget>
<output>3.14</output>

<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 + (1/5)</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">1 * (6/5)</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">(6/5) ** 2</gadget>
<output>36/25 = around 1.44</output>

<gadget id="calculator">3.14 * (36/25)</gadget>
<output>4.5216</output>

<gadget id="calculator">4.5216 - 3.14</gadget>
<output>1.3816</output>

<gadget id="calculator">1.3816 / 3.14</gadget>
<output>0.44</output>

<result>0.44</result>