The circumference of a circle is 6.28 cm, what is the area of the circle in square centimeters?
圆的周长是6.28厘米，这个圆的面积是多少平方厘米．
<gadget id="calculator">6.28 / 3.14 / 2</gadget>
<output>1</output>

<gadget id="calculator">1 ** 2</gadget>
<output>1</output>

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

<result>3.14</result>