A rectangle is 6 cm long and 2 cm wide, what is its perimeter in cm?
长方形的长6厘米，宽2厘米，它的周长是多少厘米．
<gadget id="calculator">6 + 2</gadget>
<output>8</output>

<gadget id="calculator">8 * 2</gadget>
<output>16</output>

<result>16</result>