If the height of a parallelogram is 5 cm and the base is twice the height, what is its area in square centimeters?
平行四边形的高是5厘米，底是高的2倍，它的面积是多少平方厘米．
<gadget id="calculator">5 * 2 * 5</gadget>
<output>50</output>

<result>50</result>