A section of exhaust pipe is 1 meter long, its cross-section is a square, and its side length is 2 decimeters. How many square meters of iron sheet is needed to make such an exhaust pipe?
一节排气管道长1米，它的横截面是一个正方形，边长是2分米，做一节这样的排气管至少需要多少平方米铁皮？
<gadget id="calculator">2 / 10</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 * (1/5)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/5) + (1/5)</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(2/5) * 2</gadget>
<output>4/5 = around 0.8</output>

<result>4/5 = around 0.8</result>