A rectangular flower bed is 6 meters long and 4 meters wide. What is the perimeter of this flower bed?
一个长方形花坛的长是6米，宽4米．这个花坛的周长是多少？
<gadget id="calculator">6 + 4</gadget>
<output>10</output>

<gadget id="calculator">10 * 2</gadget>
<output>20</output>

<result>20</result>