The cross-section of a sewer is trapezoidal, the upper base is 1.6 meters, the lower base is 2.8 meters, and the depth is 1.5 meters. How many square meters is its cross-sectional area?
一条下水道的横截面是梯形，上底是1.6米，下底是2.8米，深是1.5米，它的横截面面积是多少平方米？
<gadget id="calculator">1.6 + 2.8</gadget>
<output>4.4</output>

<gadget id="calculator">1.5 / 2</gadget>
<output>0.75</output>

<gadget id="calculator">4.4 * 0.75</gadget>
<output>3.3</output>

<result>3.3</result>