The side length of a square flowerbed is 20 meters, and a 1-meter-wide cement road is paved around the flowerbed. What is the area of the concrete road in square meters?
一正方形花圃的边长是20米，在这个花圃的四周铺上1米宽的水泥路．水泥路的面积是多少平方米？
<gadget id="calculator">1 * 2</gadget>
<output>2</output>

<gadget id="calculator">20 + 2</gadget>
<output>22</output>

<gadget id="calculator">22 * 22</gadget>
<output>484</output>

<gadget id="calculator">20 * 20</gadget>
<output>400</output>

<gadget id="calculator">484 - 400</gadget>
<output>84</output>

<result>84</result>