square piece of glass has a side length of (2/5) meters, what is its perimeter in meters?
一块正方形的玻璃，边长是(2/5)米，它的周长是多少米？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

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

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