There is a rectangular playground in the school, which is 28 meters long and 14 meters wide. What is its perimeter in meters?
学校里有一个长方形活动场所，长28米，宽14米，它的周长是多少米？
<gadget id="calculator">28 + 14</gadget>
<output>42</output>

<gadget id="calculator">42 * 2</gadget>
<output>84</output>

<result>84</result>