a) Name one way water sources become contaminated (dirty) in 3rd world countries?
Because people uses the bathroom from under the ground also because people litter in the streams,lake, and ocean

b) What are the dangers of water contamination?
People die from contamination because it contains 99.9% of germs and its dirty.

c) Describe (in your own words) an invention that can save people from drinking contaminated water? To stop littering in the water.

d) Why do you think everyone in 3rd world countries do not have these inventions?
Because maybe they can't afford it.