What is the length of a rectangle in centimeters, the width of 2 centimeters, and the circumference of 12 centimeters.
一个长方形的长是多少厘米厘米，宽是2厘米，周长是12厘米．
<gadget id="calculator">12 / 2</gadget>
<output>6</output>

<gadget id="calculator">6 - 2</gadget>
<output>4</output>

<result>4</result>