11. The base and height of a pair of parallelograms are 0.6 meters and 0.4 meters respectively. What is the area of a triangle with the same base and height in square meters?
11、一个平行四边形一组对应的底和高分别是0.6米和0.4米，与它等底等高的三角形的面积是多少平方米．
<gadget id="calculator">0.4 / 2</gadget>
<output>0.2</output>

<gadget id="calculator">0.6 * 0.2</gadget>
<output>0.12</output>

<result>0.12</result>