new canal was built in Honglin Village. The cross section of the canal is trapezoidal, with an upper bottom of 1.8 meters, a lower bottom of 0.8 meters and a depth of 0.5 meters. What is the cross-sectional area of this canal?
红林村新修了一条水渠，水渠的横截面是梯形，上底1.8米，下底0.8米，深0.5米．这条水渠横截面的面积是多少？
<gadget id="calculator">1.8 + 0.8</gadget>
<output>2.6</output>

<gadget id="calculator">0.5 / 2</gadget>
<output>0.25</output>

<gadget id="calculator">2.6 * 0.25</gadget>
<output>0.65</output>

<result>0.65</result>