A semi-circular chicken farm with one side against a wall and the other side surrounded by a fence. The fence is 18.84 meters long. What is the area of the chicken farm in square meters?
一个半圆形的鸡场，一面靠墙，另一面用篱笆围成．篱笆长18.84米，这个鸡场的面积是多少平方米？
<gadget id="calculator">18.84 / 3.14</gadget>
<output>6</output>

<gadget id="calculator">6 ** 2</gadget>
<output>36</output>

<gadget id="calculator">36 / 2</gadget>
<output>18</output>

<gadget id="calculator">3.14 * 18</gadget>
<output>56.52</output>

<result>56.52</result>