If a wire 16 decimeters long is formed into a square, what is the area of the square?
把一根16分米长的铁丝这成一个正方形，这个正方形的面积是多少？
<gadget id="calculator">16 / 4</gadget>
<output>4</output>

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

<result>16</result>