A circular nursery is surrounded by a 26-meter-long fence, and 0.88 meters are used at the joint. What is the size of this nursery in square meters?
用长为26米的篱笆围成一个圆形的苗圃，接头处用去了0.88米．这个苗圃的面积是多少平方米？
<gadget id="calculator">26 - 0.88</gadget>
<output>25.12</output>

<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>

<result>50.24</result>