Part of the cross-section of the Three Gorges Hydropower Dam in my country is trapezoidal. If the upper base is 36m, the lower base is 120m, and the height is 135m, what is its area in m**2.
我国三峡水电站大坝的横截面的一部分是梯形，如果上底是36m、下底是120m，高是135m，它的面积是多少m**2．
<gadget id="calculator">36 + 120</gadget>
<output>156</output>

<gadget id="calculator">135 / 2</gadget>
<output>135/2 = around 67.5</output>

<gadget id="calculator">156 * (135/2)</gadget>
<output>10_530</output>

<result>10_530</result>