A square is surrounded by a wire 12 meters long, what is the area of the square in square meters?
用一根长12米的铁丝围成一个正方形，正方形的面积是多少平方米．
<gadget id="calculator">12 / 4</gadget>
<output>3</output>

<gadget id="calculator">3 * 3</gadget>
<output>9</output>

<result>9</result>