The area of a trapezoid is 20 square meters, if its upper base, lower base and height are doubled, what is its area in square meters?
一个梯形的面积是20平方米，如果它的上底、下底和高各扩大2倍，它的面积是多少平方米．
<gadget id="calculator">20 * 2 * 2</gadget>
<output>80</output>

<result>80</result>