A trapezoid has an upper base of 3 meters, a lower base of 5 meters, and a height of 2.4 meters. What is the area?
一个梯形，上底是3米，下底是5米，高是2.4米，面积是多少．
<gadget id="calculator">3 + 5</gadget>
<output>8</output>

<gadget id="calculator">2.4 / 2</gadget>
<output>1.2</output>

<gadget id="calculator">8 * 1.2</gadget>
<output>9.6</output>

<result>9.6</result>