On a lawn, two sheep, big and small, are tied to a wooden post with 5-meter and 3-meter-long ropes respectively. What is the difference in the grass area that the two sheep can eat? (the length tied to the wooden post does not count)
在一个草坪上，用5米和3米长的绳子，分别在一个木柱上同时拴着大、小两只羊，两只羊能吃到草的面积相差多少？(拴在木柱上的长度不计)
<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

<gadget id="calculator">3 ** 2</gadget>
<output>9</output>

<gadget id="calculator">25 - 9</gadget>
<output>16</output>

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

<result>50.24</result>