What is the perimeter of two small squares whose side length is 2 cm to form a large rectangle?
边长是2厘米的两个小正方形拼成一个大长方形，它的周长是多少．
<gadget id="calculator">2 * 4 * 2</gadget>
<output>16</output>

<gadget id="calculator">2 * 2</gadget>
<output>4</output>

<gadget id="calculator">16 - 4</gadget>
<output>12</output>

<result>12</result>