A cylinder and a cone have the same volume and height. It is known that the circumference of the cylinder is 12.56dm and the height is 3dm. What is the area of the base of the cone in square decimeters?
一个圆柱和一个圆锥的体积和高都相等，已知圆柱的周长是12.56dm，高是3dm，求圆锥的底面积是多少平方分米？
<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 / 3</gadget>
<output>1</output>

<gadget id="calculator">3.14 * 4 * 3 * 1</gadget>
<output>37.68</output>

<result>37.68</result>