This is what I got hope it helps
He may have decided that a flood or something swept through and brought that with it.
A. driving. A single instance of a nuclear weapon would cause more pollution than a single instance of driving, but while millions of cars drive everyday, nuclear weapons are very rarely detonated. All the cars in the world contribute the most to pollution, especially because some countries still don't regulate the pollutants in exhaust.
Explanation:
The forms of precipitation are; drizzle, rain, snow, snow pellets, ice crystals and hailstone.
