cylinder and a cone have the same volume and height. Given that the circumference of the base of the cylinder is 12.56 cm and the height of the cylinder is 3 cm, find the area of the base of the cone.
一个圆柱和一个圆锥的体积和高都相等．已知圆柱的底面周长是12.56cm，圆柱的高是3厘米，求圆锥的底面积．
<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>