The diameter of a circular island is 50m, the middle is a circular flower bed with a diameter of 10m, and the other places are lawns. What is the size of the lawn?
一个圆形环岛的直径是50m，中间是一个直径为10m的圆形花坛，其他地方是草坪．草坪的占地面积是多少？
<gadget id="calculator">50 / 2</gadget>
<output>25</output>

<gadget id="calculator">25 ** 2</gadget>
<output>625</output>

<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

<gadget id="calculator">625 - 25</gadget>
<output>600</output>

<gadget id="calculator">3.14 * 600</gadget>
<output>1_884</output>

<result>1_884</result>