There is a 2-meter-long downspout whose cross-section is a square with a side length of 2 decimeters. How many square meters is the minimum material required to make this downpipe?
有一根2米长的落水管，横截面是边长2分米的正方形，制作这根落水管至少要材料多少平方米？
<gadget id="calculator">2 / 10</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/5) * 4 * 2</gadget>
<output>8/5 = around 1.6</output>

<result>8/5 = around 1.6</result>