A circle is formed by a wire with a length of 62.8 decimeters. What is the area of this circle in square decimeters?
用一根长62.8分米的铁丝，围成一个圆，这个圆的面积是多少平方分米．
<gadget id="calculator">62.8 / 3.14 / 2</gadget>
<output>10</output>

<gadget id="calculator">10 ** 2</gadget>
<output>100</output>

<gadget id="calculator">3.14 * 100</gadget>
<output>314</output>

<result>314</result>