A round tabletop should be surrounded by iron strips to reinforce the tabletop. The radius of the circular tabletop is 1.2 meters, how long is the iron strip at least? (π takes 3.14)
一张圆桌面要用铁皮条围成一圈，用来加固桌面．圆桌面的半径是1.2米，至少需要多长的铁皮条？(π取3.14)
<gadget id="calculator">1.2 * 2</gadget>
<output>2.4</output>

<gadget id="calculator">3.14 * 2.4</gadget>
<output>7.536</output>

<result>7.536</result>