The diameter of a circle is 2 cm. Divide it into several equal parts. After cutting it, use these small pieces of paper that are approximately isosceles triangles to form an approximate rectangle. What is the circumference of this rectangle in cm?
一个圆的直径是2cm，把它分成若干等份，剪开后，用这些近似等腰三角形的小纸片拼成一个近似的长方形，这个长方形的周长约是多少cm．
<gadget id="calculator">2 / 2</gadget>
<output>1</output>

<gadget id="calculator">3.14 * 1</gadget>
<output>3.14</output>

<gadget id="calculator">3.14 + 1</gadget>
<output>4.14</output>

<gadget id="calculator">4.14 * 2</gadget>
<output>8.28</output>

<result>8.28</result>