The base of the triangle is 2.8 meters and the height is 2.5 meters. What is the area of the parallelogram formed by two identical triangles?
三角形的底是2.8米，高是2.5米，这样两个完全相同的三角形拼成的平行四边形的面积是多少平方米．
<gadget id="calculator">2.5 / 2</gadget>
<output>1.25</output>

<gadget id="calculator">2.8 * 1.25 * 2</gadget>
<output>7</output>

<result>7</result>