An automatic rotary sprinkler irrigation device for lawns has a range of 20 meters, how many square meters can it irrigate the lawn?
一种草坪自动旋转喷灌装置的射程是20米，它能喷灌草坪的面积是多少平方米．
<gadget id="calculator">20 ** 2</gadget>
<output>400</output>

<gadget id="calculator">3.14 * 400</gadget>
<output>1_256</output>

<result>1_256</result>