a)  Name one way water sources become contaminated in 3rd world countries?One way of water sources become contaminated is by all the chemicals. The chemical go inside the water by people throwing garbage in the oceans

b) What are the dangers of water contamination?People could died because worm and other insects crawl were the water is at and the get contaminated and kids don't know that is contaminated and over 10,000 kids died of contaminated water. 

c) Describe (in your own words) an invention that can save people from drinking contaminated water?One of the inventions are the slingshot. Well the slingshot is a water purifier 

d) Why do you think everyone in 3rd world countries do not have these inventions?Maybe because they don't have the tool to do the inventions they thought of. The other they may not know about this inventions they may didn't thought of it so i think they should start to make inventions.