The sum of the upper and lower bases of a trapezoid is equal to the height. It is known that its height is 8cm, what is the area of this trapezoid in cm**2.
一个梯形的上下底的和与高相等．已知它的高是8cm，这个梯形的面积是多少cm**2．
<gadget id="calculator">8 / 2</gadget>
<output>4</output>

<gadget id="calculator">8 * 4</gadget>
<output>32</output>

<result>32</result>