Find the area of a parallelogram: the base is 0.6 meters, and the base is twice the height.
求平行四边形的面积：底是0.6米，底是高的2倍．
<gadget id="calculator">0.6 / 2</gadget>
<output>0.3</output>

<gadget id="calculator">0.6 * 0.3</gadget>
<output>0.18</output>

<result>0.18</result>