There is a sector with a radius of 5 cm and a central angle of 72°, what is the perimeter of the sector in cm?
有一个半径为5cm，圆心角为72°的扇形，这个扇形的周长是多少cm．
<gadget id="calculator">72 / 360</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">3.14 * 5 * 2 * (1/5)</gadget>
<output>6.28</output>

<gadget id="calculator">5 * 2</gadget>
<output>10</output>

<gadget id="calculator">6.28 + 10</gadget>
<output>16.28</output>

<result>16.28</result>