The school football field is a rectangle with a length of 110m and a width of 90m. What is the perimeter of the football field?
学校的足球场是一个长方形，长为110m，宽是90m，这个足球场的周长是多少．
<gadget id="calculator">110 + 90</gadget>
<output>200</output>

<gadget id="calculator">200 * 2</gadget>
<output>400</output>

<result>400</result>