A canal is trapezoidal in cross section, 3 meters wide at the mouth, 2 meters wide at the bottom, and 2 meters deep. What is its cross-sectional area in square meters?
一条水渠，横截面是梯形，渠口宽3米，渠底宽2米，渠深2米．它的横截面面积是多少平方米？
<gadget id="calculator">3 + 2</gadget>
<output>5</output>

<gadget id="calculator">2 / 2</gadget>
<output>1</output>

<gadget id="calculator">5 * 1</gadget>
<output>5</output>

<result>5</result>