The upper base of an isosceles trapezoid is 2.5cm, the lower base is 4.5cm long, and the waist length is 3cm. What is the circumference of this isosceles trapezoid in cm
一个等腰梯形的上底是2.5cm，下底长4.5cm，腰长3cm，这个等腰梯形有周长是多少cm
<gadget id="calculator">3 * 2</gadget>
<output>6</output>

<gadget id="calculator">2.5 + 4.5 + 6</gadget>
<output>13</output>

<result>13</result>