A farmer tied a sheep to a stake in the grass. If the rope for tying the sheep is 4 meters long (not counting the joints), how many square meters is the place where the sheep can eat grass?
一个农民把羊拴在草地的一个木桩上，如果拴羊的绳子长4米(接头处不计)这只羊能吃上草的地方大约有多少平方米？
<gadget id="calculator">4 ** 2</gadget>
<output>16</output>

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

<result>50.24</result>