If the perimeter of a square is 48 meters, what is its area in square meters?
一个正方形的周长是48米，它的面积是多少平方米．
<gadget id="calculator">48 / 4</gadget>
<output>12</output>

<gadget id="calculator">12 * 12</gadget>
<output>144</output>

<result>144</result>