A wire with a length of 6.28dm forms the largest circle, what is its area in dm**2.
把一根长6.28dm的铁丝围成一个最大的圆，它的面积是多少dm**2．
<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>