An isosceles trapezoid has an upper base of 8 cm, a lower base of 10 cm and a waist of 6 cm. How many centimeters of iron wire are needed to enclose this trapezoid?
一个等腰梯形上底8厘米，下底10厘米腰6厘米，围成这个梯形要多少厘米的铁丝．
<gadget id="calculator">6 * 2</gadget>
<output>12</output>

<gadget id="calculator">8 + 10 + 12</gadget>
<output>30</output>

<result>30</result>