If the area of a triangle is 280 square centimeters, what is the area of a parallelogram with the same base and height as it?
一个三角形的面积是280平方厘米，与它等底等高的平行四边形的面积是多少平方厘米．
<gadget id="calculator">280 * 2</gadget>
<output>560</output>

<result>560</result>