A sheep is tied to a post by a rope 3 meters long, what is the maximum range that the sheep can move in?
一只羊被一根长3米的绳子拴在柱子上，这只羊可以活动的最大范围是多少平方米
<gadget id="calculator">3 ** 2</gadget>
<output>9</output>

<gadget id="calculator">3.14 * 9</gadget>
<output>28.26</output>

<result>28.26</result>