Mark Twain spent his days running around with a group of other local boys engaging in hijinks, tomfoolery, and getting in all sorts of mischief. Read more: bit.ly/2gxdQYE
I would just go to spark notes. If you go there and find any that you think may be significant, come back here and I will tell you their meaning.
Answer:
air pollution can increase the risk of heath problems and can even cause deaths.