Lay turf on a circular ground with a circumference of 25.12 meters. If the turf costs 40 yuan per square meter, how much does it cost to lay turf on this ground?
在一个周长为25.12米的圆形地面上铺草皮，如果每平方米草皮要40元，则这块地面铺草皮要花多少元钱？
<gadget id="calculator">25.12 / 3.14 / 2</gadget>
<output>4</output>

<gadget id="calculator">4 ** 2</gadget>
<output>16</output>

<gadget id="calculator">3.14 * 16</gadget>
<output>50.24</output>

<gadget id="calculator">50.24 * 40</gadget>
<output>2_009.6</output>

<result>2_009.6</result>