The minute hand of a clock is 30 cm long, what is the area it sweeps in one revolution?
一座钟表的分针长30厘米，它旋转一周扫过的面积是多少？
<gadget id="calculator">30 ** 2</gadget>
<output>900</output>

<gadget id="calculator">3.14 * 900</gadget>
<output>2_826</output>

<result>2_826</result>