What is the area of a square surrounded by a wire 240 meters long?
将一根长240米的铁丝围成正方形面积是多少．
<gadget id="calculator">240 / 4</gadget>
<output>60</output>

<gadget id="calculator">60 * 60</gadget>
<output>3_600</output>

<result>3_600</result>