烟尘的排放量主要受到燃烧方式等因素的影响,煤在煤粉锅炉上燃烧几乎是完全的,排放的烟尘里几乎全是灰粉。
参考答案:对
________ by the advances in technology, many farmers have set up wind farms on their land.[ ]
A.Being encouraged
B.Encouraging
C.Encouraged
D.Having encouraged
瓦罗的《论农业》