Answer:
The answer is the first option.
Explanation:
Farming emerged because being a nomad was no longer suitable for increasing population size. Farming allowed people to stay in one place and properly feed their families, which was a definite positive impact on population size.
Goods or services that are required.
Answer:
High amounts of fluoride
Explanation:
Teeth cleaning agents can contaminate one's blood with fluoride, something that it is only healthy to accumulate a small amount of.
Answer:
Explanation:
Most electrical wire is covered in a rubber or plastic coating called insulation. ... The purpose of insulation covering the metal part of an electrical wire is to prevent accidental contact with other conductors of electricity, which might result in an unintentional electric current through those other conductors.