The area of a parallelogram is 9m**2, if its base and height are doubled, what is the area of the obtained parallelogram in m**2?
一个平行四边形的面积是9m**2，如果把它的底和高都扩大到原来的2倍，得到的平行四边形的面积是多少m**2．
<gadget id="calculator">9 * 4</gadget>
<output>36</output>

<result>36</result>