沪江小Q / 全部问题 / 能力英语 / 听力

But the researchers say it may be possible to expand the world's forests by ten percent, or an area the size of India, by 2050.
什么叫an area the size of India?

Smoke rises from a burning Indonesian forest set afire for land-clearing, 2005.
set afire for land-clearing是什么意思？

看不懂，很郁闷，求各位达人指点，谢谢！