A parallelogram is trimmed to form a square. The perimeter of the square is 16 cm. What is the area of the parallelogram in square centimeters?
一个平行四边形割补后是一个正方形，正方形的周长是16厘米，这个平行四边形的面积是多少平方厘米．
<gadget id="calculator">16 / 4</gadget>
<output>4</output>

<gadget id="calculator">4 * 4</gadget>
<output>16</output>

<result>16</result>