A sector with an arc length of 12.56cm is enclosed to form a cone. What is the area of the base of the cone in cm**2.
将一个弧长是12.56cm的扇形，围成一个圆锥体，这个圆锥体的底面积是多少cm**2．
<gadget id="calculator">12.56 / 3.14 / 2</gadget>
<output>2</output>

<gadget id="calculator">2 ** 2</gadget>
<output>4</output>

<gadget id="calculator">3.14 * 4</gadget>
<output>12.56</output>

<result>12.56</result>