Question

The water we drink usually comes from reservois, lakes, or rivers. A large number of cities use river water and dumps it bank into the river. Sometimes another city downstream uses the same water. This water may be badly polluted with chemicals and pathogenic bacteria. Many different chemical treatments are necessary to make it safe and palatable.
Many communities add some form of fluorine to their water. Fluorine in concentrations of 0.7 to 1.0 ppm (parts per million) can significantly reduce tooth dacay in children.
Smaller communities usually obtain water fron wells. Even they have problems because sometimes the ground water is contaminated by nitrates. These nitrates come from agricultural fertilizers and from the decomposition of organic waste.
What can we dor? We can fight for clear water and convince our neighbors to do the some. We can demand an end to water pollution by industries and cities. And, finally, we must know how to use the water of the earth because that is all the water we have.
Answer the questions in portuguese. Find the answers in the text.

1)O autor explica a adição de flúor na água. Porque se faz isso?
2)O que é necessário para tornar a água segura?
3)De onde vem a água que usamos em nossa cidade?
4)Alguém tem alguma ideia do que poderíamos fazer para combater a poluição da água?

Me ajudem

Answer 1

bom não jogar lixo nos rios,lagos etc

e tbm não jogar óleo pela pia isso é muito importante é nunca se pode jogar óleo pela pia